Method and system for mitigating interference by rotating antenna structures

ABSTRACT

Aspects of the subject disclosure may include, for example, obtaining data regarding interference detected in a received communication signal, and performing polarization adjusting by rotating one or more radiating elements of an antenna system such that an impact of the interference on the antenna system is minimized. Other embodiments are disclosed.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Ser. No.63/071,896, filed Aug. 28, 2020, and to U.S. Provisional Ser. No.63/231,037, filed Aug. 9, 2021. The contents of each of the foregoingare hereby incorporated by reference into this application as if setforth herein in full.

FIELD OF THE DISCLOSURE

The subject disclosure relates to detecting interference and/or passiveintermodulation (PIM) in a communications system, and performingaction(s), such as polarization adjusting and/or phaseshifting/delaying, that result in mitigation/cancellation of theinterference and/or PIM.

BACKGROUND

The deployment of fifth generation (5G) networks has made componentrequirements for cellular systems more stringent and sophisticated. Inaddition to capacity, throughput, latency, speed, and power consumptionrequirements, there is a need for multiple wireless services, bands, andnetworks to coexist and operate without impacting one another. Antennasare a key component in all wireless networks whether they are on thebase station side or the handset side. Antenna designs have evolved overthe past twenty years to meet the increasingly complex requirements ofcellular standards. For example, almost all antennas now have multiplefunctions that create conflicting antenna design requirements. Thisantenna design evolution needs to continue to meet the growing demandsof 5G networks as well as future demands of higher generation networks.

BRIEF DESCRIPTION OF THE DRAWINGS

Reference will now be made to the accompanying drawings, which are notnecessarily drawn to scale, and wherein:

FIG. 1A is a block diagram illustrating an exemplary, non-limitingembodiment of a communications network in accordance with variousaspects described herein.

FIG. 1B depicts an exemplary, non-limiting embodiment of acommunications system functioning within, or operatively overlaid upon,the communications network of FIG. 1A in accordance with various aspectsdescribed herein.

FIG. 2A is a block diagram illustrating an example, non-limitingembodiment of a system functioning within, or operatively overlaid upon,the communications network of FIG. 1A and/or the communications systemof FIG. 1B in accordance with various aspects described herein.

FIG. 2B depicts example null patterns for interference sources inaccordance with various aspects described herein.

FIG. 2C is a block diagram illustrating an example, non-limitingembodiment of a communications system having an antenna with monitoringport(s) for interference/PIM detection, and functioning within, oroperatively overlaid upon, the communications network of FIG. 1A and/orthe communications system of FIG. 1B in accordance with various aspectsdescribed herein.

FIG. 2D is a block diagram illustrating example, non-limitingembodiments of two communications systems, including a firstcommunications system having a single antenna, and a secondcommunications system having two antennas, where each of thecommunications systems may be functioning within, or operativelyoverlaid upon, the communications network of FIG. 1A and/or thecommunications system of FIG. 1B in accordance with various aspectsdescribed herein.

FIG. 2E is a block diagram illustrating an example, non-limitingembodiment of a communications system that includes the single antennaof FIG. 2D and that functions within, or is operatively overlaid upon,the communications network of FIG. 1A and/or the communications systemof FIG. 1B in accordance with various aspects described herein.

FIG. 2F is a block diagram illustrating an example, non-limitingembodiment of a communications system having an antenna and functioningwithin, or operatively overlaid upon, the communications network of FIG.1A and/or the communications system of FIG. 1B in accordance withvarious aspects described herein.

FIG. 2G is a block diagram illustrating an example, non-limitingembodiment of an antenna functioning within, or operatively overlaidupon, the communications network of FIG. 1A and/or the communicationssystem of FIG. 1B in accordance with various aspects described herein.

FIG. 2H depicts example radiation patterns of various single columnantennas in accordance with various aspects described herein.

FIG. 2J depicts example radiation patterns of an antenna with twocolumns of radiating elements and an antenna with two rows of radiatingelements in accordance with various aspects described herein.

FIG. 2K depicts an example fixed twin beam pattern in accordance withvarious aspects described herein.

FIG. 2L depicts an example radiation pattern of a first antenna arrayand an example radiation pattern of a second antenna array in accordancewith various aspects described herein.

FIG. 2M is a block diagram illustrating an example, non-limitingembodiment of polarization adjusting and associated equations inaccordance with various aspects described herein.

FIG. 2N is a block diagram illustrating an example, non-limitingembodiment of a communications system having multiple antennas each withmonitoring port(s) for interference/PIM detection, where the systemfunctions within, or is operatively overlaid upon, the communicationsnetwork of FIG. 1A and/or the communications system of FIG. 1B inaccordance with various aspects described herein.

FIG. 2P is a block diagram illustrating an example time frame in atime-division duplexing (TDD) communications system in accordance withvarious aspects described herein.

FIG. 2Q is a block diagram illustrating an example frequency-divisionduplexing (FDD) communications system in accordance with various aspectsdescribed herein.

FIGS. 2R-2X each depicts an illustrative embodiment of a method inaccordance with various aspects described herein.

FIG. 3A depicts an exemplary, non-limiting embodiment of a system inaccordance with various aspects described herein.

FIG. 3B depicts an exemplary, non-limiting embodiment of a system fordetecting PIM interferences in uplink signals of a base station inaccordance with various aspects described herein.

FIG. 3C depicts an exemplary, non-limiting embodiment of acommunications system including a virtualized interference mitigationnetwork in accordance with various aspects described herein.

FIG. 3D depicts an illustrative non-limiting embodiment of a method forperforming virtual interference mitigation in accordance with variousaspects described herein.

FIG. 4 is a block diagram of an example, non-limiting embodiment of acomputing environment in accordance with various aspects describedherein.

FIG. 5 is a block diagram of an example, non-limiting embodiment of amobile network platform in accordance with various aspects describedherein.

FIG. 6 is a block diagram of an example, non-limiting embodiment of acommunication device in accordance with various aspects describedherein.

DETAILED DESCRIPTION

Early antennas were mostly single-input, single-output (SISO), butcurrently, the majority are multiple-input, multiple-output (MIMO). MIMOis a key antenna technology for wireless communications in whichmultiple antennas are used at both the source (transmitter) and thedestination (receiver), where the antennas at each end of thecommunication circuit are combined to enhance data speed. In MIMO, eachspatial stream is transmitted from a different radio/antenna in the samefrequency channel as the transmitter. The receiver receives each streamon each of its identical radios/antennas, and reconstructs the originalstreams.

The first MIMO specifications appeared in 3rd Generation PartnershipProject (3GPP) standards at the tail end of the 3G Universal MobileTelecommunications System (UMTS) era, but it was of limited use as itwas not built into the design from the beginning. It was only with theintroduction of Long-Term Evolution (LTE) in 2008 that MIMO started tobe mainstream. The goal of MIMO is to increase data rates by sendingmultiple data streams at the same time in the same frequency, known asspatial multiplexing. In a single antenna system, one cannot sendmultiple streams of data, but with MIMO, the signals transmitted fromeach antenna take different paths to the receivers. By applying theright mix of each data stream to each transmit antenna, the signalsreceived at each receiving antenna only “see” one of the original datastreams. In effect, MIMO systems use a combination of multiple antennasand multiple signal paths to gain knowledge of the communicationschannel. By using the spatial dimension of a communications link, MIMOsystems can achieve significantly higher data rates than traditionalSISO channels.

In a communication system, a main objective for a communication channelis to increase signal to interference plus noise ratio (SINR). Let'stake a 2×2 MIMO case as an example. For the same total transmittedpower, the signal power has to be shared between the two transmitters,reducing SINR by 3 dB. This implies that MIMO gains over SISO isachieved when the SINR of the channel gets higher than is necessary tosupport the maximum SISO data rate. Such high SINR conditions occur whenthe user is near the cell center, or when interference from adjacentcells is low. When practical field deployments are taken into account,in a typical urban macro environment, it is estimated that 2×2 MIMO onlyprovides approximately 20% gain over SISO. The 2×2 MIMO configurationcan be increased by adding more antennas at each end of the link. In theoriginal 3GPP Release 8 LTE standard in 2008, 2× and 4× operation wasspecified, and 8×8 was added later in Release 10. As the number ofantennas increases, it becomes less likely that the channel will supportorthogonal transmission paths. These orthogonal paths are known asEigenmodes.

For user equipment (UEs, such as smartphones, etc.), it can be difficultto support higher order MIMO due to the space limitations for therequired number of receive antennas. For example, it took eight yearsafter Release 8 specified 4× single-user (Su)-MIMO for UEs with fourreceivers to start appearing on the market. And to take full advantageof that, networks would have to upgrade their base stations with 4transmit (Tx)/receive (Rx) antennas.

There are alternative forms of MIMO, including Su-MIMO, where multiplestreams of data can be transmitted to one user to increase peak datarates, and multi-user (Mu)-MIMO, where the same number of streams can betransmitted towards multiple users, each getting one or more streams.Mu-MIMO has the effect of increasing cell capacity, but not increasingpeak data rates to any one user over the SISO case.

Physically, an antenna can include radiating elements (or antennaelements (AEs)) arranged in interconnected columns and sharing the sameradio frequency (RF) connector. Most low frequency bands (e.g., 600megahertz (MHz) up to 2.5 gigahertz (GHz)) antennas in the marketplacetoday are multi-band (two or more bands), with each band having its ownremote electronic/electrical tilt for separate optimization capability.The radiating elements can also be combined into an antenna arraycapable of creating multiple, steerable beams by utilizing a beamformingfeed network (e.g., a butler matrix feed). Antennas for high frequencybands or millimeter (mm) waves are usually integrated with the receiver.

An antenna's radiation has a pattern (power distribution) in thehorizontal direction (an azimuth direction) and a pattern in thevertical direction usually referred to as the elevation. Antennascomprise a number of radiating elements, which may each be anorthogonally-polarized element pair, such as a dipole (e.g., acrossed-dipole) with certain properties and a particular structure.Radiating elements can be arranged in columns, and antennas that havemultiple columns can form arrays. While each radiation array may haveits own radiation pattern, the RF effect of the entire array can dependon the spacing, phase shifts, and amplitude variations between itsradiating elements. Together, these three variables can be used todescribe the array factor pattern. Multiplying the array factor patternand the element pattern can yield the overall radiation pattern of thearray antenna and define the far field.

There are various types of radiating antenna elements, such as thosewith wire and aperture elements that include dipole and monopoleelements. Aperture elements can also include slot elements. Some designsincorporate combinations of both types and can also be built overprinted circuit boards (PCBs) or micro strip patches. Each antennaelement has a radiation pattern, usually referred to as an elementpattern, whose characteristics are determined by the overall design ofthe element. Some or all of the principles, embodiments, and/or aspectsdescribed herein can apply equally to the various types of antennas.

A dipole radiating element transmits electromagnetic waves that resultin radiation around it. Near the dipole antenna, the radiated energy isoscillating as it is flowing outwards. At any instant of time, themagnetic field is “behind” the electric field by half of a period (orhalf of the wavelength). The near field is composed of two regions: thereactive near field and the radiating near field (also called theFresnel zone or region). In the far-field region (also called theFraunhofer zone or region), the field components are transverse to theradial direction of the antenna. The far-field E (electric) and H(magnetic) strength decrease by inverse law 1/r, where r is the distancefrom the antenna. Embodiments described herein define and account for anew region between/overlapping the Fresnel region and the Fraunhoferregion, namely an “intermediate” (or intermediate-field) region.

The subject disclosure describes, among other things, illustrativeembodiments of an interference/PIM cancellation system (or block) thatis capable of detecting interference/PIM in RF networks and/ormitigating (or cancelling) the interference/PIM. As the majority ofinterference/PIM generally exists in an intermediate (orintermediate-field) region (described in more detail below) thatoverlaps the near-field and far-field regions, in exemplary embodiments,the interference/PIM cancellation system is capable of cancellinginterference/PIM not based on (e.g., not based at all on or not basedonly on) nulling of far-field energy, but rather by effectingpolarization adjusting and/or phase adjusting (e.g., via electronic orphysical adjustments of signals and/or component(s) of an antennasystem) based on the detected impact of the interference/PIM in theintermediate region. In exemplary embodiments, the interference/PIMcancellation system may be configured to account (e.g., detect, cancel,or otherwise compensate) for the presence of interference/PIM in some orall of the far-field region, the intermediate region, and the near-fieldregion.

In various embodiments, polarization adjusting and/or phase adjusting(or shifting/delaying) may include performing one or more (e.g.,mechanical) adjustments to one or more components included in, orassociated with, an antenna system. In exemplary embodiments, theinterference/PIM cancellation system may include, or be included in, anadjusting mechanism or system, which may be configured to performpolarization adjusting and/or phase shifting/delaying electronically,mechanically, electromechanically, and/or the like. The one or morecomponents may include radiating elements (which may, e.g., includecrossed-dipole antenna elements, MIMO-type antenna elements, and/orother types of radiating elements) of the antenna system, or moregenerally, any structural portion of radiating elements, such as, forexample, feed port(s), ground/base plane(s), and/or the like.

As one example, one or more embodiments of the interference/PIMcancellation system may be configured to control physical movements ofone or more radiating elements of one or more antennas based on thedetected interference/PIM.

In embodiments where the interference/PIM cancellation system controlsphysical movements of radiating elements, the interference/PIMcancellation system can do so by causing radiating elements to bephysically rotated (e.g., without adjusting or moving an antennahousing). This can include, for example, causing radiating elements in afirst column of radiating elements to be rotated by a certain amount ina certain direction (e.g., from a default polarization configuration,such as +45/−45 degrees, to a different polarization configuration, suchas a +30/−60 degree orientation or the like) and either keepingradiating elements in a second column of radiating elements unchanged orcausing radiating elements in the second column to be rotated by acertain amount in a certain direction, which may provide a polarizationadjusting (e.g., mixing) effect where signals are projected in adifferent set of axes. This may result in one column receiving theinterference/PIM and the other column receiving little to none of theinterference/PIM, thereby enabling mitigation or cancellation of theinterference/PIM (e.g., via selective signal/antenna extraction/usage).

In one or more embodiments, the interference/PIM cancellation system maycontrol the physical movements of radiating elements by additionally, oralternatively, causing the radiating elements to be shifted along aradial axis of the antenna (e.g., without adjusting or moving an antennahousing). This can include, for example, causing radiating elements in afirst column of radiating elements to be shifted or displaced by acertain amount in a first direction along the radial axis, and eitherleaving radiating elements in a second column of radiating elementsunmoved or causing radiating elements in the second column to be shiftedor displaced by a certain amount in a second direction opposite thefirst direction, which may result in phase shifts or delays betweensignals associated with the radiating elements in the first column andsignals associated with the radiating elements in the second column.This may similarly result in one column receiving the interference/PIMand the other column receiving little to none of the interference/PIM,thereby enabling mitigation or cancellation of the interference/PIM(e.g., via selective signal/antenna extraction/usage).

In some embodiments, the interference/PIM cancellation system may beintegrated in a radio (e.g., a remote radio head (RRH) or remote radiounit (RRU)), and may be configured to effect some or all of thepolarization adjusting functionality and/or phase shifting/delayingfunctionality described herein. In certain embodiments, theinterference/PIM cancellation system may be integrated in an antennasystem (e.g., as part of smart antenna functionality), and may beconfigured to effect some or all of the polarization adjustingfunctionality and/or phase shifting/delaying functionality describedherein independently of a radio (e.g., a remote radio head (RRH) orremote radio unit (RRU)) and/or based on commands from the radio.

In various embodiments, the interference/PIM cancellation system may beconfigured to effect the polarization adjusting and/or phaseshifting/delaying by additionally, or alternatively, performing (e.g.,electronic) processing on (or adjustments to) signals associated withradiating elements. In such embodiments, the interference/PIMcancellation system may perform signal processing operations that definepolarizations/projections or radiation patterns for signals associatedwith the various radiating elements, which may provide theaforementioned polarization adjusting (e.g., mixing) effect wheresignals may be projected in a different set of axes. This may similarlyresult in some radiating elements receiving the interference/PIM andother radiating elements receiving little to none of theinterference/PIM, thereby enabling mitigation or cancellation of theinterference/PIM (e.g., via selective signal/antenna extraction/usage).In certain embodiments, the processing may be implemented in cases wherethe antennas are integrated with a radio (e.g., an RRH or an RRU). Forexample, as described herein, such processing may be implemented in MIMOantennas, where the radio has access to each radiating element in eachcolumn/row of the antenna via a respective controller/transceiver.

In various embodiments, the interference/PIM cancellation system mayadditionally, or alternatively, include, or be implemented, in one ormore RF devices (e.g., RF circuits or the like) configured to performpolarization adjusting and/or phase shifting/delaying byaltering/combining, in the RF domain, phase(s) and/or amplitudes ofsignals to be transmitted and/or signals that are received. Thepolarization adjusting and/or phase shifting/delaying can be based onthe level(s)/characteristic(s) of determined PIM combination(s) thatneed to be addressed.

In certain exemplary embodiments described herein, the polarizationadjusting and/or phase shifting/delaying can be additionally, oralternatively, provided by configuring or adapting one or moreproperties of certain radiating elements of an antenna (e.g., withoutadjusting or moving an antenna housing). In one or more embodiments,different shapes (or combination(s) of shapes), dimensions,electrical/magnetic properties, or a combination thereof may be selectedor defined for radiating elements of a first set (or column) ofradiating elements of an antenna relative to radiating elements of asecond set (or column) of radiating elements of the antenna. As anexample, the structure of each of a selected set of radiating elementsof an antenna system may be altered (e.g., shifted, folded, bypassed,and/or the like). As another example, the structure of each of aselected set of radiating elements of an antenna system may besubstituted with a different structure. By virtue of the difference inproperties between the first and second columns of radiating elements(which can, for example, provide a polarization adjusting and/or phaseshifting/delaying effect), the amount of interference/PIM that isreceived, or whether interference/PIM is received at all, may beselectively controlled. For example, this may similarly result in someradiating elements receiving the interference/PIM and other radiatingelements receiving little to none of the interference/PIM, therebyenabling mitigation or cancellation of the interference/PIM (e.g., viaselective signal/antenna extraction/usage).

As also described herein, one or more embodiments of theinterference/PIM cancellation system may include monitoring elementsthat are distinct from the main radiating elements of an antenna, andthat are configured to detect interference/PIM in the far-field region,the intermediate region, and/or the near-field region. In someimplementations, the main radiating elements of an antenna mayadditionally, or alternatively, be configured to detect interference/PIMin one or more of these regions.

In various embodiments, the interference/PIM cancellation system mayinclude hardware and/or software components (which may, for example, beintegrated in the antenna or located externally to the antenna)configured to effect polarization adjusting and/or phaseshifting/delaying by performing signal conditioning of uplink signals ina manner that (partially or fully) cancels interference/PIM therefrom.

It is to be appreciated and understood that various embodimentsdescribed herein may address interference/PIM in the near-field orintermediate-field regions, and may have minimal to no impact todownlink signals in the far-field region (e.g., in a portion of thefar-field region that excludes the intermediate-field region).

It is also to be appreciated and understood that the various embodimentsthat provide polarization adjusting and/or phase shifting/delaying (forexample, by performing adjustments for component(s) associated with anantenna system, such as radiating elements, structural portions ofradiating elements, etc., by processing of signals associated withradiating elements, by defining of different (e.g., structural)properties for different sets of radiating elements of antenna(s), etc.)and/or signal conditioning to cancel detected interference/PIM may becombined in any manner and used together in any way (e.g., physicalrotation of radiating elements and processing of signals associated withradiating elements may be performed together; physical shifting ofradiating elements, signal conditioning, and defining of differentstructural properties for different sets of radiating elements may beperformed together; etc.).

In some implementations, in the various embodiments in which adjustmentsare made for component(s) associated with an antenna system (e.g.,adjustments for structural portion(s) of radiating elements, physicalrotation/shifting of radiating elements, etc.) and/or processing ofsignals associated with radiating elements is performed, some or all ofthese adjustments and/or signal processing may be performedautomatically—e.g., by one or more smart detection/cancellationdevices/systems/algorithms—based on the detected interference/PIM.

In other implementations, in the various embodiments in whichadjustments are made for component(s) associated with an antenna system(e.g., adjustments for structural portion(s) of radiating elements,physical rotation/shifting of radiating elements, etc.) and/orprocessing of signals associated with radiating elements is performed,some or all of these adjustments and/or signal processing may beperformed manually—e.g., by one or more operators or administrators inlight of the detected interference/PIM. In such implementations, one ormore preset conditions or settings (e.g., relating to particularadjustments, such as rotation angles, shifting displacement values,polarizations/projections, etc.) may be available for user selection,and may, when selected, cause the appropriate polarization adjustmentsand/or phase shifts/delays to be effected accordingly.

Based on an analysis of known or likely interference/PIM levels,characteristics, and/or combinations, proper selection of polarizationadjusting parameters/values, phase shifts/delays, and/or the like may bedetermined and utilized to manipulate antenna systems. By providingpolarization adjusting and/or phase shifting/delaying (e.g., viaadjustments to structural portion(s) of radiating elements of theantenna system, physical rotation/shifting of radiating elements of theantenna system, processing of signals associated with radiatingelements, and/or defining of different (e.g., structural) properties fordifferent sets of radiating elements), as described herein, downlinksignals can be manipulated or otherwise influenced in a way thatminimizes or reduces the amount of interference/PIM that is received inthe uplink, which can improve overall uplink performance and coverage.Radiating elements, and more generally, an antenna system may,therefore, be designed, configured, and/or controlled in order tooptimize (or improve) the near-field and far-field regions forinterference/PIM reduction. The principle of orthogonality between thedifferent modes of transmission can also be taken into account, whereinterference/PIM source(s) minimally interact with transmissions,thereby reducing the level of interference/PIM detected/received by acommunications system.

While the distinction between field components is clear mathematically,the fields overlap (e.g., the demarcation of the spatial field regionsmay be subjective), and thus there may be substantial far-field andnear-field radiative components in the closest-in near-field reactiveregion. In various implementations, alternative methodologies orapproaches may be employed, including approaches that focus onminimizing reflected energy based on the summation of the near field,the intermediate field, and the far field. This can be achieved, forexample, by simulating an antenna's near field and optimizing (orimproving) its properties.

In exemplary embodiments, various techniques described herein, includingmethods for polarization adjusting and/or phase shifting/delaying andthe like, can be exploited in time-division duplex (TDD) systems and/orfrequency-division duplex (FDD) systems to relax, loosen, or otherwisedecrease the number of system implementation requirements, such as thoserelating to guard times/bands in TDD and frequency separation in FDD.

Various techniques described herein for manipulating/altering/adjustingsignal transmission/reception and/or component(s) of an antenna system(e.g., radiating elements, structural portion(s) of radiating elements,etc.) may be applied to the uplink and/or downlink in a TDDcommunications system in order to reduce or eliminate the guard band. Inexemplary embodiments, the polarization of the uplink can be adjustedrelative to the polarization of the downlink, or vice versa, such thatthe uplink polarization and the downlink polarization are different fromone another. For instance, in cases where one or more MIMO antennas thatprovide parallel transmissions are employed in a TDD system,polarization adjusting may be applied for some or all of the radiatingelements utilized during downlink operations such that the polarizationthereof is in a first polarization, and may be similarly applied forsome or all of the radiating elements utilized during uplink operationssuch that the polarization thereof is in a different (e.g., orthogonal)polarization. Doing so creates an additional dimension of separationthat permits a smaller guard band to be used, which can provide improvednetwork speeds. In extreme cases, guard bands can even be eliminated,where downlink and uplink transmissions may overlap or coexist withoutinterference by virtue of the use of different, orthogonalpolarizations.

Various techniques described herein for manipulating/altering/adjustingsignal transmission/reception and/or component(s) of an antenna system(e.g., radiating elements, structural portion(s) of radiating elements,etc.) may also be applied to the uplink in a TDD communications systemin order to address any direct interference with FDD system signalsand/or any PIM generated by mixing of FDD system signals. In exemplaryembodiments, polarization adjusting can be employed in the TDD system toseparate the TDD uplink from FDD system signals. Here, the TDD uplinkmay be deployed in particular polarization(s) that enable the TDD uplinkto avoid receiving signals from the FDD systems and/or any PIM generatedby mixing of FDD system signals.

Various techniques described herein for manipulating/altering/adjustingsignal transmission/reception and/or component(s) of an antenna system(e.g., radiating elements, structural portion(s) or radiating elements,etc.) may also be applied to the uplink and/or downlink in an FDDcommunications system in order to reduce or eliminate the need forduplexers (e.g., by relaxing or loosening duplexer requirements). Inexemplary embodiments, for example, polarization adjusting, can beemployed in an FDD system (e.g., as an additional way) to separate thedownlink and uplink frequencies. Here, the downlink and the uplink maybe deployed in different (e.g., orthogonal) polarizations. That is, forexample, the polarization of the uplink can be adjusted relative to thepolarization of the downlink, or vice versa, such that the uplinkpolarization and the downlink polarization are different from oneanother. Doing so creates an additional dimension of separation thatpermits the use of fewer or less sophisticated duplexers (e.g.,duplexers with fewer stages), since signal gain (in dB) that mightotherwise be offered through the use of more duplexer stages can insteadbe provided via polarization adjusting. This can advantageously enablemassive MIMO implementations in FDD. In extreme cases, duplexers caneven be eliminated altogether by virtue of the use of different,orthogonal polarizations.

One or more aspects of the subject disclosure include a device,comprising a processing system including a processor and associated withan antenna system, and a memory that stores executable instructionsthat, when executed by the processing system, facilitate performance ofoperations. The operations can include obtaining data regardinginterference detected in a received communication signal. Further, theoperations can include performing polarization adjusting by rotating oneor more radiating elements of the antenna system such that an impact ofthe interference on the antenna system is minimized.

One or more aspects of the subject disclosure include a method. Themethod can comprise obtaining data regarding interference originatingfrom one or more interference sources. Further, the method can includemitigating, by an adjusting mechanism associated with an antenna system,the interference by performing polarization adjusting via rotation ofradiating elements of the antenna system.

One or more aspects of the subject disclosure include a non-transitorymachine-readable medium, comprising executable instructions that, whenexecuted by a processing system including a processor and associatedwith an antenna system, facilitate performance of operations. Theoperations can include receiving data regarding interference present ina received communication signal. Further, the operations can includeperforming polarization adjusting by causing one or more radiatingelements of the antenna system to be rotated such that the interferenceis mitigated.

Other embodiments are described in the subject disclosure.

Referring now to FIG. 1A, a block diagram is shown illustrating anexample, non-limiting embodiment of a system 100 in accordance withvarious aspects described herein. For example, system 100 canfacilitate, in whole or in part, detection of interference/PIM in acommunications system and performing of action(s), such as polarizationadjusting and/or phase shifting/delaying, as described herein, thatresult in mitigation/cancellation of the interference/PIM. Inparticular, a communications network 125 is presented for providingbroadband access 110 to a plurality of data terminals 114 via accessterminal 112, wireless access 120 to a plurality of mobile devices 124and vehicle 126 via base station or access point 122, voice access 130to a plurality of telephony devices 134, via switching device 132 and/ormedia access 140 to a plurality of audio/video display devices 144 viamedia terminal 142. In addition, communications network 125 is coupledto one or more content sources 175 of audio, video, graphics, textand/or other media. While broadband access 110, wireless access 120,voice access 130 and media access 140 are shown separately, one or moreof these forms of access can be combined to provide multiple accessservices to a single client device (e.g., mobile devices 124 can receivemedia content via media terminal 142, data terminal 114 can be providedvoice access via switching device 132, and so on).

The communications network 125 includes a plurality of network elements(NE) 150, 152, 154, 156, etc. for facilitating the broadband access 110,wireless access 120, voice access 130, media access 140 and/or thedistribution of content from content sources 175. The communicationsnetwork 125 can include a circuit switched or packet switched network, avoice over Internet protocol (VoIP) network, Internet protocol (IP)network, a cable network, a passive or active optical network, a 4G, 5G,or higher generation wireless access network, WIMAX network,UltraWideband network, personal area network or other wireless accessnetwork, a broadcast satellite network and/or other communicationsnetwork.

In various embodiments, the access terminal 112 can include a digitalsubscriber line access multiplexer (DSLAM), cable modem terminationsystem (CMTS), optical line terminal (OLT) and/or other access terminal.The data terminals 114 can include personal computers, laptop computers,netbook computers, tablets or other computing devices along with digitalsubscriber line (DSL) modems, data over coax service interfacespecification (DOCSIS) modems or other cable modems, a wireless modemsuch as a 4G, 5G, or higher generation modem, an optical modem and/orother access devices.

In various embodiments, the base station or access point 122 can includea 4G, 5G, or higher generation base station, an access point thatoperates via an 802.11 standard such as 802.11n, 802.11ac or otherwireless access terminal. The mobile devices 124 can include mobilephones, e-readers, tablets, phablets, wireless modems, and/or othermobile computing devices.

In various embodiments, the switching device 132 can include a privatebranch exchange or central office switch, a media services gateway, VoIPgateway or other gateway device and/or other switching device. Thetelephony devices 134 can include traditional telephones (with orwithout a terminal adapter), VoIP telephones and/or other telephonydevices.

In various embodiments, the media terminal 142 can include a cablehead-end or other TV head-end, a satellite receiver, gateway or othermedia terminal 142. The display devices 144 can include televisions withor without a set top box, personal computers and/or other displaydevices.

In various embodiments, the content sources 175 include broadcasttelevision and radio sources, video on demand platforms and streamingvideo and audio services platforms, one or more content data networks,data servers, web servers and other content servers, and/or othersources of media.

In various embodiments, the communications network 125 can includewired, optical and/or wireless links and the network elements 150, 152,154, 156, etc. can include service switching points, signal transferpoints, service control points, network gateways, media distributionhubs, servers, firewalls, routers, edge devices, switches and othernetwork nodes for routing and controlling communications traffic overwired, optical and wireless links as part of the Internet and otherpublic networks as well as one or more private networks, for managingsubscriber access, for billing and network management and for supportingother network functions.

FIG. 1B depicts an exemplary, non-limiting embodiment of atelecommunication communications system 180 functioning within, oroperatively overlaid upon, the communications network 100 of FIG. 1A inaccordance with various aspects described herein. For example, system180 can facilitate, in whole or in part, detection of interference/PIMin a communications system and performing of action(s), such aspolarization adjusting and/or phase shifting/delaying, as describedherein, that result in mitigation/cancellation of the interference/PIM.As shown in FIG. 1B, the telecommunication system 180 may include mobileunits 182, 183A, 183B, 183C, and 183D, a number of base stations, two ofwhich are shown in FIG. 1B at reference numerals 184 and 186, and aswitching station 188 to which each of the base stations 184, 186 may beinterfaced. The base stations 184, 186 and the switching station 188 maybe collectively referred to as network infrastructure.

During operation, the mobile units 182, 183A, 183B, 183C, and 183Dexchange voice, data or other information with one of the base stations184, 186, each of which is connected to a conventional land linecommunication network. For instance, information, such as voiceinformation, transferred from the mobile unit 182 to one of the basestations 184, 186 is coupled from the base station to the communicationnetwork to thereby connect the mobile unit 182 with, for example, a landline telephone so that the land line telephone may receive the voiceinformation. Conversely, information, such as voice information may betransferred from a land line communication network to one of the basestations 184, 186, which in turn transfers the information to the mobileunit 182.

The mobile units 182, 183A, 183B, 183C, and 183D and the base stations184, 186 may exchange information in either narrow band or wide bandformat. For the purposes of this description, it is assumed that themobile unit 182 is a narrowband unit and that the mobile units 183A,183B, 183C, and 183D are wideband units. Additionally, it is assumedthat the base station 184 is a narrowband base station that communicateswith the mobile unit 182 and that the base station 186 is a widebanddigital base station that communicates with the mobile units 183A, 183B,183C, and 183D.

Narrow band format communication takes place using, for example,narrowband 200 kilohertz (KHz) channels. The Global system for mobilephone systems (GSM) is one example of a narrow band communication systemin which the mobile unit 182 communicates with the base station 184using narrowband channels. Alternatively, the mobile units 183A, 183B,183C, and 183D communicate with the base station 186 using a form ofdigital communications such as, for example, 3GPP Long Term Evolution(LTE), code-division multiple access (CDMA), Universal MobileTelecommunications System (UMTS), or other next, generation wirelessaccess technologies. LTE, for instance, is a wireless broadbandcommunication standard that covers many different frequency bandsdepending on the geographical region. The terms narrowband and widebandreferred to above can be replaced with sub-bands, concatenated bands,bands between carrier frequencies (carrier aggregation), and so on,without departing from the scope of the subject disclosure.

The switching station 188 is generally responsible for coordinating theactivities of the base stations 184, 186 to ensure that the mobile units182, 183A, 183B, 183C, and 183D are constantly in communication with thebase station 184, 186 or with some other base stations that aregeographically dispersed. For example, the switching station 188 maycoordinate communication handoffs of the mobile unit 182 between thebase station 184 and another base station as the mobile unit 182 roamsbetween geographical areas that are covered by the two base stations.

In various circumstances, the telecommunication system 180, and moreparticularly, one or more of the base stations 184, 186 can beundesirably subjected to interference. Interference can representemissions within band (narrowband or wideband), out-of-band interferers,interference sources outside cellular (e.g., TV stations, commercialradio or public safety radio), interference signals from other carriers(inter-carrier interference), interference signals from UEs operating inadjacent base stations, PIM, and so on. Interference can represent anyforeign signal that can affect communications between communicationdevices (e.g., a UE served by a particular base station).

FIG. 2A is a block diagram illustrating an example, non-limitingembodiment of a system 200 functioning within, or operatively overlaidupon, the communications network 100 of FIG. 1A and/or thecommunications system 180 of FIG. 1B in accordance with various aspectsdescribed herein. As depicted, the system 200 can include an antenna (orantenna system) 201. In various embodiments, the antenna 201 may includemultiple radiating elements. In one or more embodiments, the antenna 201may include multiple columns and/or rows of radiating elements, formingan antenna array. In certain embodiments, the antenna 201 may includemultiple arrays or panels. As shown in FIG. 2A, the antenna 201 can beassociated with various spatial regions, including a reactive near-fieldregion 200 c, a radiating near-field region 200 d, a far-field region200 f, and an intermediate region 200 i. One or more UEs/users 200 u maybe located in the far-field region 200 f. The intermediate region 200 imay include a zone that overlaps a portion of the radiating near-fieldregion 200 d and a portion of the far-field region 200 f.

In various antenna deployments, antennas (or more particularly, theuplink) may be subject to interference and/or PIM—e.g., a PIM source 200p. PIM interference may be due to nonlinearities external to antennasthat, when subjected to electromagnetic waves emitted by antennaelements in the downlink frequency band, generate reflections atfrequencies in the uplink frequency band. PIM interference may also bedue to antenna(s) of a base station transmitting and receiving indownlink and uplink frequency bands that are close to one another, ordue to different antennas of different base stations transmitting infrequency bands that are close to one another. In these cases,intermodulation of signals transmitted in different (but sufficientlyclose) frequencies can result in passive signals falling into an uplinkfrequency band. In any case, interference/PIM decreases uplinksensitivity and thus negatively impacts uplink coverage, reliability,performance, and data speeds.

As depicted in FIG. 2A, the antenna 201 can be disposed or deployed on astructure, such as a building rooftop. It is to be appreciated andunderstood that the antenna 201 can be deployed in any suitable manner.As one example, the antenna 201 may be mounted on one or more towerswhere few or no objects may be located nearby (e.g., an unobstructedantenna on a tower), and thus a far-field representation may beadequate. As another example, multiple antennas 201 may be locatedwithin close proximity to one another (e.g., within a threshold distancefrom one another), where the antennas 201 may or may not haveoverlapping degrees of coverage, and thus the near-field region may havean impact on antenna performance. As yet another example, one or moreantennas 201 may be deployed on building rooftop(s) in densely-populatedareas (e.g., towns or cities). In this example, the antennas 201 may belocated within close proximity to one another and may have overlappingdegrees of coverage and/or be obstructed by nearby external objects,such that the near-field and intermediate field regions may have animpact on antenna performance.

The far field (e.g., the far-field region 2000 may be defined by adistance r>>2L²/(λ), where L is the length of the antenna and λ is thewavelength of a transmitted signal. Antenna specifications are generallybased on the far-field region. In the far-field region, the electric andmagnetic fields are perpendicular to each other, the ratio of E/H is thefree space propagation, and the antenna pattern is not a function of thedistance r. The near field, and more particularly the reactivenear-field (e.g., the reactive near-field region 200 c), can be definedby r<λ/2π. In the radiating near-field region (or the Fresnel region)(e.g., the radiating near-field region 200 d), for λ/2π<r<2L²/(λ), theradiated power density is greater than the reactive power density and1/r³ is very small, but the 1/r and 1/r² terms are still dominant. Forthe intermediate region (e.g., the intermediate region 200 i), wherer>2L²/(A), the term 1/r is larger than the other terms but not yetdominant. In all of the regions other than the far-field region, theelectric and magnetic fields are not perpendicular. Various exemplaryembodiments described herein account for the transition region—i.e., theintermediate region—between/overlapping the near-field and far-fieldregions, which can be represented differently, mathematically.

The electric and magnetic field equations for a dipole, such as a dipoleantenna element of the antenna 201 (e.g., in a case where the antenna201 includes dipole elements) may include:

$\begin{matrix}{{{Er} = {\frac{{IoL}\;\cos\;\theta\; e^{{- j}\;{\omega{\lbrack{t - \frac{r}{c}}\rbrack}}}}{2\pi ɛ_{o}}( {\frac{1}{cr^{2}} + \frac{1}{j\omega r^{3}}} )}};} & ( {{EQ}\mspace{14mu} 1} ) \\{{E_{\theta} = {\frac{{IoL}\;\sin\;\theta\; e^{{- j}\;{\omega{\lbrack{t - \frac{r}{c}}\rbrack}}}}{4\pi ɛ_{o}}( {\frac{j\;\omega}{c^{2}r} + \frac{1}{cr^{2}} + \frac{1}{j\omega r^{3}}} )}};} & ( {{EQ}\mspace{14mu} 2} ) \\{{E_{\varphi} = 0};} & ( {{EQ}\mspace{14mu} 3} ) \\{{{H\;\varphi} = {\frac{{IoL}\;\sin\;\theta\; e^{{- j}\;{\omega{\lbrack{t - \frac{r}{c}}\rbrack}}}}{4\pi}( {\frac{j\omega}{cr} + \frac{1}{r^{2}}} )}};{and}} & ( {{EQ}\mspace{14mu} 4} ) \\{{H_{r} = {{0\mspace{14mu}{and}\mspace{14mu} H_{\theta}} = 0}},} & ( {{EQ}\mspace{14mu} 5} )\end{matrix}$

where E_(r) and H_(r) are the radial electric and magnetic fieldscomponents,where E_(φ) and H_(φ) are the azimuth electric and magnetic fieldscomponents, andwhere E_(θ) and H_(θ) are the polar electric and magnetic components.Here, I_(o) is the peak value of the current flowing in the radiatingelement (e.g., dipole), ε_(o) is the permittivity or dielectric constantof free space, ω=2πf, where f is the frequency, c is the speed of light,L is the length of the dipole, and r is the distance from the dipole.

For the intermediate region, when r>L²/(λ), the second and the thirdterms in E_(θ) become zero, and the second term in H_(φ) becomes zero,resulting in the following equations:

$\begin{matrix}{{{Er} \cong \frac{{IoL}\;\cos\;\theta\; e^{{- j}\;{\omega{\lbrack{t - \frac{r}{c}}\rbrack}}}}{2\pi ɛ_{o}cr^{2}}};} & ( {{EQ}\mspace{14mu} 6} ) \\{{{E\;\theta} \cong \frac{j\;\omega\;{IoL}\;\sin\;\theta\; e^{{- j}\;\omega\;{t{\lbrack{t - \frac{r}{c}}\rbrack}}}}{4\pi ɛ_{o}c^{2}r}};{and}} & ( {{EQ}\mspace{14mu} 7} ) \\{{H\;\varphi} \cong {\frac{j\;\omega\;{IoL}\;\sin\;\theta\; e^{{- j}\;\omega\;{t{\lbrack{t - \frac{r}{c}}\rbrack}}}}{4\pi cr}.}} & ( {{EQ}\mspace{14mu} 8} )\end{matrix}$

For the far-field region, when r>>L²/(λ), E_(r) becomes zero, the secondand third terms in E_(θ) become zero, and the second term in H_(φ)becomes zero, resulting in the following equations:

$\begin{matrix}{{{E\theta} \cong \frac{j\;\omega\;{IoL}\;\sin\;\theta\; e^{{- j}\;\omega\;{t{\lbrack{t - \frac{r}{c}}\rbrack}}}}{4\pi ɛ_{o}c^{2}r}};{and}} & ( {{EQ}\mspace{14mu} 9} ) \\{{H\;\varphi} \cong {\frac{j\;\omega\;{IoL}\;\sin\;\theta\; e^{{- j}\;\omega\;{t{\lbrack{t - \frac{r}{c}}\rbrack}}}}{4\pi cr}.}} & ( {{EQ}\mspace{14mu} 10} )\end{matrix}$

Antennas are typically designed based on the desired behavior in thefar-field region—i.e., in accordance with certain design goals relatingto beamwidth, half-power bandwidth, directivity, and back loberadiation. Antennas are also designed not to generate PIM. Smartantennas are configured to minimize interference, generally byidentifying the direction of the interference and creating nulls in thatdirection to avoid reception and transmission. For example, FIG. 2Bdepicts example null patterns 202 for interference sources in accordancewith various aspects described herein. In certain embodiments, theantenna 201 may be operated using nulling techniques in which the energyreflected from the far-field is detected and used for optimizationdecisions. In such embodiments, the performance of the antenna(s) maythus be optimized (or improved) based on (e.g., based only on) the farfield and not on the near field or the intermediate field.

Because the majority of interference/PIM is usually in the intermediateregion, it can be advantageous to adapt/adjust antenna configurationsand/or perform signal processing that enables such interference/PIM tobe accounted for (i.e., detected, cancelled, or otherwise compensatedfor). Take, for example, a typical signal, which may be a sum of desireduplink signal(s) and undesired signal(s). A desired signal may be asignal originating from an end user device that is typically in the farfield of an antenna. PIM, on the other hand, may be generated from acombination of far-field, intermediate-field, and/or near-fieldinterfering signals, a substantial portion of which may originate fromthe intermediate-field region of the antenna. Thus, in a case where thefar-field region for a 700 MHz, 2 meter (m) long antenna starts at about19 m (e.g., about 120 feet) from the antenna, and the radiating nearfield starts at about 2.8 m (e.g., about 10 feet) from the antenna, mostof the interference/PIM signals originate from sources located in theradiating near field or the intermediate region (e.g., 10 to 120 feetfrom the antenna). In exemplary embodiments, therefore, the antenna 201may be configured to perform optimization based on near-field,intermediate-field, and/or far-field regions rather than the far-fieldregion alone. In various embodiments, the antenna 201 may be capable ofcancelling or mitigating interference/PIM as described herein.

FIG. 2C is a block diagram illustrating an example, non-limitingembodiment of a communications system 203 having an antenna 201 a withmonitoring port(s) for interference/PIM detection, and functioningwithin, or operatively overlaid upon, the communications network 100 ofFIG. 1A and/or the communications system 180 of FIG. 1B in accordancewith various aspects described herein. The communications system 203 mayinclude a radio 203 r (e.g., a remote radio head or unit) and aninterference/PIM detection control device 203 d. Although not shown inFIG. 2C, in one or more embodiments, the radio 203 r may becommunicatively coupled to the interference/PIM detection control device203 d. In various embodiments, the antenna 201 a may be the same as, maybe similar to, or may otherwise correspond to the antenna 201 of FIG.2A. As shown in FIG. 2C, the antenna 201 a may include multiple columnsof (e.g., main) radiating elements 203 g and one or more columns ofmonitoring antenna elements 203 m, which may be referred to herein as“patches.” It will be appreciated and understood that the term patch, asused herein, may not imply and/or may not be limited to patchantennas—that is, patches described herein can be constructed from anysuitable antenna design, including but not limited to patch antennas,and can represent one or more antennas that form a patch. In variousembodiments, the monitoring elements 203 m may be included in,incorporated into, or otherwise built into, the antenna 201 a, and maybe configured to detect interference/PIM signals originating from theintermediate-field region. The monitoring elements 203 m may beconfigured to maximize the reception of such signals from theintermediate-field region, and minimize the reception of signals fromthe far-field region of the antenna 201 a.

The antenna 201 a and/or the main radiating elements 203 g therein maybe any shape or combination of shapes with any suitable dimensions,polarizations, etc. The antenna 201 a may also include any suitablenumber of columns and rows of radiating elements 203 g. The monitoringelements 203 m may also be any shape or combination of shapes with anysuitable dimensions, polarizations, etc., and can be configured based oninterference/PIM cancellation needs. The monitoring elements 203 m canbe disposed amongst the radiating element 203 g in any suitable manner,such as between various columns of the radiating elements 203 g, betweenradiating elements of the same column of radiating elements 203 g,and/or the like.

As shown in FIG. 2C, the antenna 201 a may include, for the mainradiating elements 203 g, one or more outputs 203 t on the antenna 201a's housing that can be communicatively coupled (e.g., via analog/RFline(s)) to the radio 203 r. The antenna 201 a may also include, asmonitoring port(s) for the monitoring elements 203 m, one or moreoutputs 203 u on the housing that can be communicatively coupled (e.g.,via analog/RF line(s) or other line(s) suitable to carry data from themonitoring elements 203 m) to the interference/PIM detection controldevice 203 d. In various embodiments, the interference/PIM detectioncontrol device 203 d may, through the use of digital signal processing,analyze and/or examine the interference/PIM signals received from themonitoring elements 203 m, and determine appropriate cancellationmeasures/decisions. Although FIG. 2C shows the interference/PIMdetection control device 203 d as being an external device, in certainembodiments, the interference/PIM detection control device 203 d (e.g.,some or all of the functionality thereof) may instead be included, orintegrated, in the antenna 201 a or the radio 203 r.

In various embodiments, and as shown in FIG. 2C, the antenna 201 a may(e.g., optionally) include an interference/PIM cancellation block 203 cintegrated therein. The interference/PIM cancellation block 203 c may beconfigured to provide mitigation or cancellation of undesiredinterference/PIM signals, such as by performing signal conditioning onsignals received by the radiating elements 203 g. In some embodiments,the output of the monitoring elements 203 m can be utilized within theantenna (e.g., by the interference/PIM cancellation block 203 c) toaddress the interference/PIM. In these embodiments, the interference/PIMcancellation block 203 c may include some or all of the functionalitiesof the interference/PIM detection control device 203 d (and/or otherrelated cancellation devices) for detecting interference/PIM in theoutput of the monitoring elements 203 m and/or for determining andapplying cancellation measures. Alternatively, the interference/PIMcancellation block 203 c may (e.g., after the output of the monitoringelements 203 m is provided to the interference/PIM detection controldevice 203 d for analysis) obtain data/command(s) from theinterference/PIM detection control device 203 d with regard tointerference/PIM mitigation or cancellation, and effect themitigation/cancellation based on the data/command(s).

In certain embodiments, the output of the monitoring elements 203 m canadditionally, or alternatively, be routed externally to one or moreother ports (e.g., on the antenna 201 a's housing) coupled to one ormore other systems/devices to obtain additional benefits, such asdetermining additional cancellation measures, obtaining insight intocharacteristics/location of the PIM source, performing additional signalanalyses and data collection, and/or the like.

Cancellation measures may include dynamic modification of antennaparameters, control of multiple antennas as a cluster, and/or informingother cancellation devices in the RF or digital path (including, forexample, a Common Public Radio Interface (CPRI) or enhanced CPRI(eCPRI)) of the interference/PIM conditions, which may enable such othercancellation devices to cancel with greater efficiency and accuracy.Crest Factor Reduction (CFR) algorithms are focused on reducing thedynamic range of a power amplifier without sacrificing too much errorvector magnitude (EVM). CFR can help the amplifier operate moreefficiently. In one or more embodiments, one or more CFR algorithms canbe used—e.g., within a radio or remote radio head—for interference/PIMcancellation. In certain embodiments, the parameters/control of the CFRalgorithm(s) can be coupled with (e.g., provided to) theinterference/PIM cancellation block 203 c and/or the interference/PIMdetection control device 203 d for use in determining/applyingcancellation measures. Alternatively, the CFR algorithm(s) can becoupled with (e.g., provided to) other interference/PIM cancellationdevices disposed in the RF or digital path to achieve increasedcancellation performance.

It is to be appreciated and understood that the interference/PIMcancellation block 203 c may be a high-level representative block thatprovides one or more functions of various embodiments described herein,including, for example, embodiments that enable mitigation/cancellationof interference/PIM by causing adjustment(s) to be made to one or morecomponent(s) of an antenna system (such as adjustments to structuralportions of radiating elements, physical rotation/shifting of radiatingelements, and/or the like) and/or by processing signals associated withradiating elements.

In various embodiments, the antenna 201 a may include different sets ofmain radiating elements. For example, the antenna 201 a may include afirst set of radiating elements configured to operate in a firstfrequency band, and a second set of radiating elements configured tooperate in a second frequency band (see, for example, FIG. 2G, where anantenna may include a first set of radiating elements 207 g, 207 hconfigured to operate in one frequency band, and a second set ofradiating elements 207 g′, 207 h′ configured to operate in a differentfrequency band). In certain embodiments, some or all of the monitoringelements 203 m may be incorporated in the second set of radiatingelements and configured for interference/PIM detection in the secondfrequency band.

In various embodiments, some or all of the first set of radiatingelements and/or the second set of radiating elements may be configuredfor interference/PIM detection in the first/second frequency bands. Inthese embodiments, the monitoring elements 203 m (and thus the outputs203 t) may or may not be included or needed. In implementations wherethe monitoring elements 203 m and outputs 203 u are not included orneeded, the detected interference/PIM signals may be routed via theoutputs 203 t; alternatively, the detected interference/PIM signals maynevertheless be routed via the outputs 203 t, but the outputs 203 t maybe communicatively coupled to the first/second set of main radiatingelements (rather than to the monitoring elements 203 m).

FIG. 2D is a block diagram 204 illustrating example, non-limitingembodiments of two communications systems, including a firstcommunications system 204 v having a single antenna 201 b, and a secondcommunications system 204 w having two antennas 201 b′ and 201 b″, whereeach of the communications systems 204 v and 204 w may be functioningwithin, or operatively overlaid upon, the communications network 100 ofFIG. 1A and/or the communications system 180 of FIG. 1B in accordancewith various aspects described herein. As shown in FIG. 2D, the antenna201 b of the first communications system 204 v may include a column 204m of radiating elements 204 g communicatively coupled to an RRU 204 i(for a certain frequency band, such as Band 1), and a column 204 n ofradiating elements 204 h communicatively coupled to an RRU 204 k (for acertain frequency band, such as Band 2). As also depicted, the antenna201 b′ of the second communications system 204 w may include a column204 m′ of radiating elements 204 g′ communicatively coupled to an RRU204 i′ (for a certain frequency band, such as Band 1), and the antenna201 b″ of the second communications system 204 w may include a column204 n′ of radiating elements 204 h′ communicatively coupled to an RRU204 k′ (for a certain frequency band, such as Band 2). In variousembodiments, one or more of the antennas 201 b, 201 b′, 201 b″ may bethe same as, may be similar to, or may otherwise correspond to theantenna system 201 of FIG. 2A.

In some embodiments, in the first communications system 204 v, theantenna 201 b may include multiple columns of radiating elements (e.g.,multiple columns 204 m and/or multiple columns 204 n) and/or there maybe additional antennas 201 b communicatively coupled to the RRUs 204 i,204 k or to additional RRUs. Additionally, in some embodiments, in thesecond communications system 204 w, the antenna 201 b′ may includemultiple columns of radiating elements (e.g., multiple columns 204 m′),the antenna 201 b″ may include multiple columns of radiating elements(e.g., multiple columns 204 n′), and/or there may be additional antennas201 b′ and/or 201 b″ communicatively coupled to the RRUs 204 i′, 204 k′or to additional RRUs. Furthermore, while the radiating elements 204 g,204 h, 204 g′, and 204 h′ are shown as crossed-dipole elements, it is tobe appreciated and understood that each of the antennas 201 b, 201 b′,and 201 b″ may additionally, or alternatively, include one or more othertypes of elements.

In either of the first communications system 204 v and the secondcommunications system 204 w, mixing of Band 1 and Band 2 downlinksignals (DL1 and DL2, respectively) can result in interference/PIM. Forexample, PIM can produce energy in (e.g., that “lands” in) either theBand 1 uplink channel (UL1) or the Band 2 uplink channel (UL2), causinginterference. In exemplary embodiments, various radiating elements ofthe first and second communications systems 204 v and 204 w may becapable of being physically rotated. In various embodiments, forexample, the radiating elements 204 h of column 204 n of the antenna 201b may be configured to physically rotate (204 z) (e.g., about a radialaxis of the antenna 201 b, shown as the X-axis) and/or the radiatingelements 204 g of column 204 m of the antenna 201 b may be configured tophysical rotate (e.g., about the X-axis). Similarly, in variousembodiments, the radiating elements 204 h′ of column 204 n′ of theantenna 201 b″ may be configured to physically rotate (204 z′) (e.g.,about the X-axis) and/or the radiating elements 204 g′ of column 204 m′of the antenna 201 b′ may be configured to physically rotate (e.g.,about the X-axis). Physical rotation of orthogonal dipoles in one columnrelative to orthogonal dipoles in another column can be equivalent to,or result in, polarization adjusting (e.g., mixing), where signals areprojected in a different set of axes, which can impact the near-field(and/or intermediate-field) signal strength in (e.g., each of) theorthogonal dipole transmitting/receiving antennas, thereby enablinginterference/PIM mitigation or cancellation.

In the first communications system 204 v, the RRUs 204 i and 204 k andthe antennas (i.e., columns of radiating elements) may be 2Tx and 2Rx.Both bands (Bands 1 and 2) may be transmitted using separatecrossed-dipole columns 204 m and 204 n within a single antenna 201 b,where the separate RRUs 204 i and 204 k share the antenna 201 b, whereBand 1 is associated with two ports of the antenna 201 b and with thefirst column 204 m of crossed-dipole elements 204 g, and where Band 2 isassociated with another two ports of the antenna 201 b and with thesecond column 204 n of crossed-dipole elements 204 h. Here, by rotatingthe crossed-dipole elements associated with Band 1 (e.g., some or all ofthe radiating elements 204 g in the column 204 m), the crossed-dipoleelements associated with Band 2 (e.g., some or all of the radiatingelements 204 h in the column 204 n), or both (e.g., some or all of theradiating elements 204 g in the column 204 m and some or all of theradiating elements 204 h in the column 204 n), the receipt/detection ofPIM by the antenna 201 b (or by the first communications system 204 voverall) can be altered. Similarly, in the second communications system204 w, separate 2Tx and 2Rx RRUs 204 i′ and 204 k′ and antennas (i.e.,antennas 201 b′ and 201 b″) may be employed. Here, by rotating thecrossed-dipole elements associated with Band 1 (e.g., some or all of theradiating elements 204 g′ in the column 204 m′ of the antenna 201 b′),the crossed-dipole elements associated with Band 2 (e.g., some or all ofthe radiating elements 204 h′ in the column 204 n′ of the antenna 201b″), or both (e.g., some or all of the radiating elements 204 g′ in thecolumn 204 m′ of the antenna 201 b′ and some or all of the radiatingelements 204 h′ in the column 204 n′ of the antenna 201 b″), thereceipt/detection of PIM by the antennas 201 b′ and/or 201 b″ (or by thesecond communications system 204 w overall) can be altered.

In exemplary embodiments, an interference/PIM cancellation block (aninterference/PIM cancellation block 204 c of FIG. 2E, which may be thesame as, may be similar to, or may correspond to the interference/PIMcancellation block 203 c of FIG. 2C) may be configured to providerotational control of the radiating elements of the first and/or secondcommunications systems 204 v and 204 w. In various embodiments, thechoice of which column of radiating elements to rotate and/or therotational amount or angle can be based on determined interference/PIMlevels or characteristics, which may be detected by monitoring elements(e.g., the monitoring elements 203 m of FIG. 2C and/or aninterference/PIM detection control device similar to theinterference/PIM detection control device 203 d) or may be known toexist or determined to likely exist (e.g., in accordance with historicaland/or measurement data). Based on such interference/PIM information,the interference/PIM cancellation block may cause various radiatingelements (or column(s) of radiating elements) to rotate accordingly. Forexample, in the first communications system 204 v, the interference/PIMcancellation block may cause (e.g., each of) the radiating elements 204h in the column 204 n of the antenna 201 b to rotate from a defaultpolarization (e.g., of +45/−45 degrees) to a different polarization(e.g., of +30/−60 degrees or another orthogonal combination), while theradiating elements 204 g in the column 204 m may remain in the defaultpolarization (e.g., of +45/−45 degrees). In any case, antennaconfigurations with a variety of differently polarized columns ofradiating elements (e.g., a mix of vertically-polarized radiatingelements and cross-polarized radiating elements; or columns of radiatingelements with different orthogonal polarization combinations) can,therefore, be obtained.

Appropriate rotation of select radiating elements (or columns ofradiating elements) may result in, for example, one or more columns ofradiating elements receiving or detecting some or all of theinterference/PIM and one or more other columns of radiating elementsreceiving or detecting little to none of the interference/PIM, withminimal to no impact to the far field pattern. In exemplary cases,therefore, interference/PIM may be eliminated (zeroed out) or neareliminated with respect to a first column of orthogonal dipoles, and asecond column of orthogonal dipoles may receive/detect some or all ofthe interference/PIM, thus enabling a receiving system to select thesignal from the first column of orthogonal dipoles (the “clean” signal)for use. Here, while diversity may be lost (e.g., about 3 dB),interference/PIM cancelation of 15+dB can be achieved, resulting in anet 12+dB benefit. Configuring the communications systems such thatcertain column(s) of radiating elements are essentially interference/PIMfree can also enable selective use thereof for certain types of traffic(e.g., high priority traffic or the like).

It is to be appreciated and understood that the interference/PIMcancellation block may be configured to cause rotation of radiatingelements in any suitable manner. In exemplary embodiments, for example,an antenna (e.g., the antennas 201 b, 201 b′, and/or 201 b″) may includeone or more motor assemblies (e.g., a shaft and linear motor or othergear and rod mechanism, such as the motor(s) 207 w and/or 207 y andshaft(s) 207 x and/or 207 z shown in diagram 207 of FIG. 2G)communicatively coupled to radiating elements and configured to controlrotary motion thereof (e.g., to fractions of a degree in accuracy andwith minimal to no overshoot, or the like). In some embodiments, eachcolumn of radiating elements may be (e.g., independently) controllableby a respective motor assembly. In one or more embodiments, theinterference/PIM cancellation block may be configured to cause radiatingelements to rotate via remote electronic/electrical tilt.

FIG. 2E is a block diagram illustrating an example, non-limitingembodiment of a communications system 205 that includes the singleantenna 201 b of FIG. 2D and that functions within, or is operativelyoverlaid upon, the communications network 100 of FIG. 1A and/or thecommunications system 180 of FIG. 1B in accordance with various aspectsdescribed herein. As shown in FIG. 2E, the antenna 201 b may (e.g.,similar to the antenna 201 a of FIG. 2C) include an interference/PIMcancellation block (e.g., an interface/PIM cancellation block 204 c),and may be communicatively coupled to a radio (e.g., a radio 204 r) viaoutputs (e.g., outputs 204 t) and to an interference/PIM detectioncontrol device (e.g., an interference/PIM detection control device 204d) via other outputs (e.g., outputs 204 u). Here, and as described abovewith respect to FIG. 2D, either or both of the column 204 m of radiatingelements 204 g and the column 204 n of radiating elements 204 h may berotatably controllable by the interference/PIM cancellation block 204 cbased on detected levels/characteristics of interference/PIM.

FIG. 2F is a block diagram illustrating an example, non-limitingembodiment of a communications system 206 having an antenna 201 c, andfunctioning within, or operatively overlaid upon, the communicationsnetwork 100 of FIG. 1A and/or the communications system 180 of FIG. 1Bin accordance with various aspects described herein. As shown in FIG.2F, the antenna 201 c may include a column 206 m of radiating elements206 g communicatively coupled to a dual band RRU 206 j, and a column 206n of radiating elements 206 h communicatively coupled to the dual bandRRU 206 j. In various embodiments, the antenna 201 c may be the same as,may be similar to, or may otherwise correspond to the antenna system 201of FIG. 2A. The dual band RRU 206 j and dual band antennas (i.e.,columns of radiating elements) may be 4Tx and 4Rx. While FIG. 2F shows asingle RRU and a single antenna, it is to be appreciated and understoodthat, in alternate embodiments, separate RRUs and separate antennas maybe employed for Band 1 and Band 2.

In exemplary embodiments, the crossed-dipole elements (e.g., one or moreof the radiating elements 206 g of the column 206 m) associated with oneband, such as Band 1, may be linearly shiftable (206 s) along the X-axisand/or the crossed-dipole elements (e.g., one or more of the radiatingelements 206 h of the column 206 n) associated with the other band, suchas Band 2, may be linearly shiftable (206 s′) along the X-axis. Shiftingone column of radiating elements relative to the other column ofradiating elements can alter the reception/detection of PIM by theantenna 201 c (or by the communications system 206 overall). Inparticular, when a distance d₁ between the column 206 m and the PIMsource 200 p is equal to a distance d₂ between the column 206 n and thePIM source 200 p, the downlink carriers may sum constructively. Incontrast, if the difference between the distances d₁ and d₂ is half ofthe wavelength, the downlink carriers may sum deconstructively, reducingor eliminating the PIM.

In exemplary embodiments, an interference/PIM cancellation block (notshown in FIG. 2F, but that may be the same as, may be similar to, or maycorrespond to the interference/PIM cancellation block 203 c of FIG. 2Cand/or the interference/PIM cancellation block 204 c of FIG. 2E) may beconfigured to control physical shifting (206 s, 206 s′) of radiatingelements of the antenna 201 c. In various embodiments, the choice ofwhich column of radiating elements to shift and/or the displacementamount and direction of shifting can be based on determinedinterference/PIM levels or characteristics, which may be detected bymonitoring elements (e.g., the monitoring elements 203 m of FIG. 2Cand/or an interference/PIM detection control device similar to theinterference/PIM detection control device 203 d) or may be known toexist or determined to likely exist (e.g., in accordance with historicaland/or measurement data). Based on such interference/PIM information,the interference/PIM cancellation block may cause various radiatingelements (or column(s) of radiating elements) to displace along theX-axis accordingly. For example, the interference/PIM cancellation blockmay cause (e.g., each of) the radiating elements 206 h of the column 206n of the antenna 201 c to shift in the X-direction by a certain amount,and may cause (e.g., each of) the radiating elements 206 g of the column206 m of the antenna 201 c to shift in the opposite direction by acertain amount, and/or the like.

Appropriate (e.g., linear) displacement of select radiating elements (orcolumns of radiating elements) may result in, for example, one or morecolumns of radiating elements receiving or detecting some or all of theinterference/PIM and one or more other columns of radiating elementsreceiving or detecting little to none of the interference/PIM, withminimal to no impact to the far field pattern. Similar to theembodiments described above with respect to FIGS. 2D and 2E, forexample, in exemplary cases, interference/PIM may be eliminated (zeroedout) or near eliminated with respect to a first column of orthogonaldipoles, and a second column of orthogonal dipoles may receive/detectsome or all of the interference/PIM, thus enabling a receiving system toselect the signal from the first column of orthogonal dipoles (the“clean” signal) for use.

It is to be appreciated and understood that the interference/PIMcancellation block may be configured to cause shifting of radiatingelements in any suitable manner. In exemplary embodiments, for example,an antenna (e.g., the antenna 201 c) may include one or more motorassemblies communicatively coupled to radiating elements and configuredto control motion thereof along the radial axis of the antenna. In someembodiments, each column of radiating elements may be (e.g.,independently) controllable by a respective motor assembly.

In some embodiments, physical rotation/shifting of monitoring elements,such as the monitoring elements 203 m of FIG. 2C, may also be effectedin order to adjust interference/PIM detection parameters of thoseelements.

Some antennas include columns of 2, 4, and (sometimes) 8 radiatingelements. As the number of radiating elements increases, the beam widthin the elevation pattern decreases. In other words, adding moreradiating elements in the same column of an antenna can permit narrowerbeamwidths in the elevation direction. An antenna may generally haveless than 10 degrees in the elevation plane. In some instances, and invarious embodiments described herein, a single column antenna may have aradiation pattern in the azimuth plane of about 65 to 90 degrees ofhalf-power beamwidth. FIG. 2H depicts example radiation patterns 208 a,208 b, and 208 c of various single column antennas (e.g., a 2-radiatingelement antenna, a 4-radiating element antenna, and an 8-radiatingelement antenna, respectively) in accordance with various aspectsdescribed herein. In some embodiments, one or more of the single columnantennas shown in FIG. 2H may be the same as, may be similar to, or mayotherwise correspond to the antenna 201 of FIG. 2A.

In certain instances, an antenna may include multiple columns or rows ofradiating elements, where each of the radiating elements may beconnected to a respective transceiver. In such instances, longitudinalor azimuth beamforming scenarios may depend on the phase and amplitudeof the signal at the input of the antenna. FIG. 2J depicts exampleradiation patterns 210 a and 210 b of an antenna with two columns ofradiating elements and an antenna with two rows of radiating elements,respectively, in accordance with various aspects described herein. Insome embodiments, one or more of the antennas shown in FIG. 2J may bethe same as, may be similar to, or may otherwise correspond to theantenna 201 of FIG. 2A.

Beamforming enables the creation of sophisticated radiation patternswith increased signal strength or sensitivity in a certain directionand/or reduced interference to and from another direction. The quantityof radiating elements in the beamforming array may affect the complexityof the beamforming patterns. For example, an antenna array consisting ofeight elements may allow for a higher degree of pattern shaping ascompared to a four-element array.

Different amplitude and phase values may result in beamforming. Invarious embodiments, a matrix network can create fixed beam forming. Incertain embodiments, the antenna 201 of FIG. 2A, for example, mayinclude one or more fixed twin beam antennas. A fixed beam antenna canprovide pre-set alignment of the main beams while providing optimaloverlap, which has multiple applications in cell splitting. FIG. 2Kdepicts an example fixed twin beam radiation pattern 211 in accordancewith various aspects described herein. Implementation of antennaconfigurations in which multiple (e.g., twin) beams or the like areprovided/utilized are described herein. The antenna configurations ofFIGS. 2D and 2F, for example, may enable port monitoring and beamswitching to selectively identify/capture “clean” and/orinterference/PIM signals.

For an M-element equally-spaced linear array that uses variableamplitude element excitations and phase scanning, the array factor canbe represented by:

$\begin{matrix}{{{{AF}(\Phi)} = {\sum\limits_{m = 0}^{M - 1}{A_{m}e^{{jm}(\frac{{{{\omega d\cos}{(\phi_{m})}} + \delta})}{c}}}}},} & ( {{EQ}\mspace{14mu} 11} )\end{matrix}$

where

${\delta = {\frac{\omega}{c}d\mspace{14mu}{\cos( \varphi_{0} )}}},$

ω=2πf, f is the frequency, and d is the spacing between the radiatingelements.

In exemplary embodiments, one or more properties of certain radiatingelements of an antenna may be configured or adapted to effectpolarization adjusting and/or phase shifting/delaying, and therebyachieve interference/PIM mitigation or cancellation. In one or moreembodiments, different shapes, dimensions, electrical/magneticproperties, or a combination thereof may be selected or defined forradiating elements of a first column of radiating elements of an antennarelative to radiating elements of a second column of radiating elementsof the antenna. By virtue of the difference in properties between thefirst and second columns of radiating elements, the amount ofinterference/PIM that is received, or whether interference/PIM isreceived at all, may be selectively controlled. Take, for example, an8-radiating element antenna. Designing or adapting half (4) of the 8radiating elements in one configuration and the other four in adifferent configuration can provide a degree of freedom for optimizing(or improving) near-field and intermediate-field regions. In otherwords, with 4 radiating elements of each kind, the far field may“appear” similar to a case where all 8 radiating elements are identical,but the near-field and intermediate-field regions of the “mix” of 4radiating elements of one configuration and 4 radiating elements ofanother configuration may “appear” differently, thereby enablingmitigation/cancellation of interference/PIM in the near-field and/orintermediate-field regions without impacting the far field. Processingrequirements may include the need to update amplitude and phase beamweight values (e.g., on the order of 1 millisecond (ms)). Additionally,complex algorithms (which may be implemented in the radio, a basebandprocessing unit, and/or a third-party device) may be utilized to supportpattern synthesis.

In various embodiments, the interference/PIM cancellation block may beconfigured to cause one or more properties, such as a structure, of oneor more radiating elements to be changed or altered, in any suitablemanner. In exemplary embodiments, for example, one or more motorassemblies may be communicatively coupled to radiating element(s) (orone or more structural portions thereof) and/or other structuralcomponent(s), and configured to control motion of such radiatingelement(s) and/or structural portion(s)/component(s) such that anoverall structure of the radiating element(s) or each of the radiatingelement(s) is altered. In some embodiments, each column of radiatingelement(s) and/or associated structural portion(s)/component(s) may be(e.g., independently) controllable by a respective motor assembly.

Therefore, in a general case, having radiating elements in a firstcolumn of an antenna with structures/properties that are different fromthe structures/properties of radiating elements in a second column ofthe antenna, can provide signal phase manipulation, enabling generationof different (e.g., left/right) radiation patterns, such as two or morelobes.

For an M-element not equally spaced linear array that uses variableamplitude element excitations and phase scanning, the array factor canbe represented by:

$\begin{matrix}{{{A{F(\Phi)}} = {\sum_{m = 0}^{M - 1}{A_{m}e^{j{m(\frac{\omega\;{{d\cos}{({{(\phi_{m})} + \delta})}}}{c}}}}}}.} & ( {{EQ}\mspace{14mu} 12} )\end{matrix}$

Here, in exemplary embodiments, each radiating element may be made to beslightly different (e.g., in structure or other property) from itsneighboring radiating element and/or the radiating elements may bearranged in an interleaved 2 equally spaced array pattern or othersuitable pattern, such that different or desired near-field propertiesare obtained. Optimizing the configuration of radiating elements in thisway can enable PIM reduction without impacting the far field.

In various embodiments, beamforming by phase shifting can be achievedusing ferrite phase shifters at RF or intermediate frequency (IF). Incertain embodiments, phase shifting can be additionally, oralternatively, implemented via digital signal processing at baseband.

In this way, whether antenna embodiments described herein passively oractively (e.g., based on feedback from an integrated or external device,such as the interference/PIM detection control device 203 d of FIG. 2C,the interference/PIM detection control device 204 d of FIG. 2E, or otherdetection device(s)) treat legitimate signals (e.g., free, or near-free,of interference/PIM) differently from non-legitimate signals,interference/PIM can be reduced or cancelled (e.g., via selectivesignal/antenna extraction/usage, such as via selection of radiatingelements of the antenna).

In some embodiments, altering of one or more properties of monitoringelement(s), such as the monitoring elements 203 m of FIG. 2C, may alsobe effected in order to adjust interference/PIM detection parameters ofthose elements.

The Antenna Interface Standards Group (AISG) defines and maintainsstandards for controlling/monitoring the interface between a basestation and various equipment at a tower top, such as antennas withremote electrical tilt, amplifiers, RRHs, etc. Various versions of basecommunication standards have been released, including version 3 (AISGv3.0). AISG v3.0 provides for device control ports connectable todifferent base station controllers, as well as controller mapping of RFsystem interconnections of devices connected to a central bus. AISG v3.0specifies the interface between a base station and antenna line devices(ALDs), which may be manageable units (e.g., subunits, such as remoteelectrical tilt, top-mounted amplifiers, antenna sensors, etc.)associated with base station antenna systems, and describes the commonbehavior of ALDs with AISG interfaces. An ALD may have one or more AISGinterfaces controllable by a base station.

In exemplary embodiments, the AISG interface can be leveraged tofacilitate overall control of interference monitoring/detection, and/orpolarization adjusting and/or phase shifting/delaying (such as viaphysical movement/alteration of radiating elements (or structuralportions) thereof and/or via electronic-based adjustments). An AISGinterface may be included in an antenna (e.g., antenna 201 b or thelike, as shown in FIG. 2E by reference numeral 205 i; although AISGinterface(s) may be included in other antenna embodiments, such as theantenna 201 of FIG. 2A, the antenna 201 a of FIG. 2C, the antenna 201 cof FIG. 2F, etc.), and may be communicatively coupled to aninterference/PIM cancellation block (e.g., the interference/PIMcancellation block 204 c or the like) and/or an interference/PIMdetection control device (e.g., the interference/PIM detection controldevice 204 d or the like). The AISG interface may be incorporated in anantenna in any suitable manner—e.g., the AISG interface may beimplemented in an interference/PIM cancellation block; the AISGinterface may be separate from, but integrated with, an interference/PIMcancellation block; the AISG interface may include an interference/PIMcancellation block; or the like. In exemplary embodiments, the AISGinterface may be controllable (e.g., by the interference/PIMcancellation block) to cause the physical movements (e.g., rotation,shifting, etc.) of radiating elements and/or changes or alterations toproperties/structures of radiating elements described herein. In someembodiments, for example, the AISG interface may be coupled to one ormore motors or the like for effecting such movements/alterations, andmay provide appropriate signal(s) thereto based on data/commands fromthe interference/PIM cancellation block. In this way, one or morestandard interfaces, such as AISG interface(s), can be employed tofacilitate polarization adjusting and/or phase shifting/delaying tomitigate/cancel interference/PIM in a communication system.

Smart antenna system technology relates to intelligent antennas, phasedarrays, Spatial Division Multi Access (SDMA), spatial processing,digital beamforming, adaptive antenna systems, and others. Smart antennasystems are customarily categorized as either switched beam with afinite number of fixed, predefined patterns or combining strategies(sectors) or as adaptive arrays with an infinite number of patterns(scenario-based) that are adjusted in real-time. The dual purpose of asmart antenna system is to augment the signal quality of the radio-basedsystem through more focused transmission of radio signals, whileenhancing capacity through increased frequency reuse. In exemplaryembodiments, the newly-identified intermediate-field region can beleveraged to optimize (or improve) antenna performance.

Active Antenna Systems (AAS) use flexible cell splits (e.g., vertical orhorizontal) and/or beamforming to provide increased system flexibilityand performance. An AAS base station uses multiple transceivers on anantenna array to produce a radiation pattern that can be dynamicallyadjusted. Spatial selectivity in both the transmit and receivedirections is important. For example, compared to fixed beam antennas,an AAS may experience different spatial selectivity since it does notachieve full spatial selectivity until after digital baseband processingof the multiple elements in the array.

With recent advances in active antenna technology, it is possible todeploy base stations with a large number of antenna elements to enhancecell capacity and coverage. Antenna elements can be deployed intwo-dimensional (2D) arrays, providing horizontal (azimuth) as well asvertical beamforming. In urban environments, with high rise buildings,this can improve indoor coverage and increase capacity. Wirelessnetworks with base stations having a large number of antenna elementsare known as massive MIMO, or Elevation Beamforming/Full Dimension(EB/FD) MIMO systems. Beamforming can rely on some or all of thetechniques described herein to further optimize (or improve)performance.

For a 2D array of M by N elements not equally spaced and that usesvariable amplitude element excitations and phase scanning, the arrayfactor can be represented by:

$\begin{matrix}{{{A{F(\Phi)}} = {\sum_{m = 0}^{M - 1}{\sum_{n = 0}^{N - 1}{A_{mn}e^{j{m(\frac{{{\omega{\hat{r}.{\overset{\_}{r}}_{mn}}} + \delta_{mn}})}{c}}}}}}},} & ( {{EQ}\mspace{14mu} 13} )\end{matrix}$

where {circumflex over (r)}, r _(mn)=d sin(θ) cos(φ)+d sin(θ) sin(φ)+dcos(θ).

FIG. 2L depicts an example radiation pattern 212 a of a first antennaarray 212 c (i.e., an 8×8 array) and an example radiation pattern 212 bof a second antenna array 212 d (e.g., a 16×16 array) in accordance withvarious aspects described herein. In various embodiments, one or more ofthe antenna arrays 212 c and 212 d may correspond to the antenna 201 ofFIG. 2A.

Examples of fixed beam techniques include butler matrix, Blass matrixand Wullenweber array. Adaptive beam forming methods include the blockadaptive method and the sample-by-sample method. Block implementation ofthe adaptive beamformer uses a block of data to estimate the adaptivebeamforming weight vector, and is known as sample matrix inversion(SMI). The sample-by-sample method updates the adaptive beamformingweight vector with each sample. Sample-by-sample methods include theleast mean square (LMS) algorithm, the constant modulus algorithm (CMA),the least square CMA, and the recursive least square (RLS) algorithm. Invarious embodiments, some or all of these methods/algorithms may beadapted and utilized. For example, some or all of thesemethods/algorithms may be modified to account for variations in antennaarray elements.

FD-MIMO systems are distinct from the MIMO systems of LTE andLTE-Advanced standards in that a large number of antennas is employed atthe eNodeB (eNB). As the number of eNB antennas M by N increases,cross-correlation of two random channel realizations becomes zero suchthat inter-user interference in the downlink can be controlled via asimple linear precoder. Such a benefit can be realized, however, onlywhen perfect channel state information (CSI) is available at the eNB.While CSI acquisition in TDD systems is relatively simple due to thechannel reciprocity, such is not the case for FDD systems, where thetime variation and frequency response of the channel are measured viadownlink reference signals (RS) and returned to the eNB after thequantization. Identifying potential issues of CSI acquisition anddeveloping the proper solutions are, therefore, important for successfulcommercialization of FD-MIMO systems. Interference/PIM minimization orcancellation, as described herein, can have a direct impact thereto thatbe exploited using non-symmetrical elements.

FD-MIMO systems also employ active antennas with 2D planar arrays. Inactive antenna-based systems, gain and phase are controlled by theactive components, such as a power amplifier (PA) and a low noiseamplifier (LNA) attached to each antenna element. In a 2D-structuredantenna array, the radio wave can be controlled on both the vertical(elevation) and horizontal (azimuth) directions such that control of thetransmit beam in three-dimensional (3D) space is possible. This type ofwave control mechanism is also referred to as 3D beamforming. 2D AAS canaccommodate a large number of antennas without increasing deploymentspace.

In smart antenna beamforming, when 64 linear antenna arrays, forexample, are deployed in a horizontal direction, under the assumptionthat the antenna spacing is half of the wavelength (λ/2) and the systemis using an LTE carrier frequency (e.g., 2 GHz), horizontal spacing of 3m may be required. Due to the limited space on a rooftop or mast, such aspacing requirement might be burdensome for most cell sites. Incontrast, when antennas are arranged in a square array, relatively smallspacing is needed for a 2D antenna array (e.g., 1.0 m×0.5 m with adual-polarized 8×8 antenna array). Embodiments for interference/PIMminimization or cancellation, described herein, can enable furtherreductions in the sizes of such arrays.

Smart antenna systems (which can leverage the SDMA method) employadaptive algorithm(s) that enable signal extraction. While an antenna byitself is capable of converting electrical signals into electromagneticwaves or vice versa, the adaptive algorithm(s) provide the intelligenceof a smart antenna system. An adaptive algorithm can be designed toaccount for challenges that prevent an antenna from combining bands.Embodiments for interference/PIM minimization or cancellation, describedherein, can enable further enhancements to adaptive algorithm(s).

In exemplary embodiments, an interference/PIM cancellation system may beconfigured to effect polarization adjusting and/or phaseshifting/delaying by performing processing (e.g., mathematically) on (oradjustments to) signals associated with (e.g., to be transmitted by)various radiating elements, based on detected interference/PIM. Invarious embodiments, methods employed by a MIMO 2D array antenna forbeamforming and nulling (of interference at certain points in space),for example, can be modified or otherwise replaced with advancedalgorithm(s) configured to effect rotation of certain group(s) ofradiating elements of the antenna. Whereas embodiments described abovewith respect to FIGS. 2D and 2E involve physical rotation of radiatingelements to effect polarization adjusting, here, “electronic” rotationcan be employed to create polarization selective nulling patterns.Changing the polarization of certain radiating elements' transmissionsand receptions, while maintaining orthogonality, can reduce/eliminateinterference/PIM (e.g., in the near-field or intermediate-fieldregions), with minimal to no effect to downlink signal patterns at userequipment (UEs) (e.g., in the far field). In various embodiments, thepolarization of signals to be transmitted and the polarization ofreceived signals may be different from one another.

FIG. 2M is a block diagram illustrating an example, non-limitingembodiment 213 of polarization adjusting and associated equations inaccordance with various aspects described herein. As shown in FIG. 2M,the polarization of signals transmitted by an orthogonally-polarizedpair of elements, such as a crossed-dipole antenna 213 u, 213 v, may bechanged. Here, suppose signals s₁(t) and 52(t) are transmitted by the+45 degree dipole 213 u and the −45 degree dipole 213 v,respectively—that is, where signal s₁(t) may be transmitted with a +45degree polarization and signal s₂(t) may be transmitted with a −45degree polarization. In a case where (e.g., based on a desire tomitigate or cancel interference/PIM, such as likely PIM combinations)there is a need to “rotate” or modify the polarization of the signals₁(t) to 90 degrees (e.g., horizontal) and the polarization of thesignal s₂(t) to 0 degrees (e.g., vertical), equations 213 p can beapplied to derive new signals s₁′(t) and s₂′(t). As shown, the newsignals can be computed by mixing (e.g., gain mixing) the originalsignals s₁(t) and s₂(t), which is equivalent to a “rotation” of thecrossed-dipole antenna by an angle 213 w (here, for example, 45 degreesin the counter-clockwise direction). In this way, when signals s₁′(t)and s₂′(t) are transmitted from the +45 dipole and the −45 dipole, it isequivalent to transmitting s₁(t) and s₂(t) from dipoles oriented at 90degrees and 0 degrees. Selection of certain polarizations and/orradiation patterns can be viewed as a projection of signals in differentaxes.

It is to be appreciated and understood that the weights in polarizationadjusting are real values (rather than complex values), and operate by“mathematically” rotating receive antenna dipoles to match thepolarization of a desired signal. It is also to be appreciated thatselection of radiating elements (e.g., which columns of radiatingelements) for which polarization adjusting is to be applied may be basedon the level(s)/characteristic(s) of determined PIM combination(s) thatneed to be addressed. Additionally, polarization adjusting can beeffected for transmit only, for receive only, or for both transmit andreceive. In cases where polarization adjusting is effected for bothtransmit and receive, in one or more embodiments, the polarizationsselected for the transmit and the receive may be the same, similar, ordifferent and/or the polarization adjusting may be performed in the samemanner, in a similar manner, or differently for the transmit and thereceive. In one or more embodiments, a radio, such as an RRH or RRU(which may have individual access to each radiating element of theantenna), may be configured to perform the electronic/mathematicrotation. For example, a MIMO 2D array antenna may be integrated withthe radio. In some respects, this may be advantageous overimplementations where a radio is not integrated with the antenna(s),such as where one vendor supplies the radio and a different vendorsupplies the antenna(s), which may be the case in some or all of thesystems described above with respect to FIGS. 2D, 2E, and 2F, and whichmay require a concerted effort between the vendors to arrive at thedesired technical implementation.

It is further to be appreciated and understood that, since beamformingscanning generally occurs in the azimuth plane and beam narrowinggenerally occurs in the elevation plane, algorithms that rely on thenear field and the intermediate-field may result in tighter relationsbetween azimuth and elevation antenna performance.

In various embodiments, the interference/PIM cancellation system mayadditionally, or alternatively, include, or be implemented, in one ormore RF devices (e.g., RF circuits or the like) configured to performpolarization adjusting and/or phase shifting/delaying byaltering/combining, in the RF domain, phase(s) and/or amplitudes ofsignals to be transmitted and/or signals that are received. Thepolarization adjusting and/or phase shifting/delaying can be based onthe level(s)/characteristic(s) of determined PIM combination(s) thatneed to be addressed.

FIG. 2N is a block diagram illustrating an example, non-limitingembodiment of a communications system 214, in which multiple antennas201 d, 201 d′, 201 d″, and 201 d′″ (each with monitoring port(s) forinterference/PIM detection) are deployed, functioning within, oroperatively overlaid upon, the communications network 100 of FIG. 1Aand/or the communications system 180 of FIG. 1B in accordance withvarious aspects described herein. In one or more embodiments, themultiple antennas 201 d, 201 d′, 201 d″, and 201 d′″ (e.g., as acombination) may correspond to the antenna 201 of FIG. 2A. In variousembodiments, one or more of the antennas 201 d, 201 d′, 201 d″, and 201d′″ may be similar to one or more of the antenna 201 a of FIG. 2C andthe antenna 201 b of FIG. 2E. For example, in certain embodiments, oneor more of the antennas 201 d, 201 d′, 201 d″, and 201 d′″ may includemultiple columns of (e.g., main) radiating elements and (e.g.,optionally) one or more columns of monitoring antenna elements (e.g.,similar to the monitoring elements 203 m of FIG. 2C).

As shown in FIG. 2N, the communications system 214 may include a radio214 r (e.g., a remote radio head or unit), an interference/PIM detectioncontrol device 214 d, a baseband-based interference/PIM canceller 214 b,and an RF-based interference/PIM canceller 214 f. As depicted, one ormore of the antennas 201 d, 201 d′, 201 d″, and 201 d′″ may include afirst set of output(s) communicatively coupled to the radio 214 r viathe RF-based interference/PIM canceller 214 f, and a second set ofoutput(s) interconnected with one another and communicatively coupled tothe interference/PIM detection control device 214 d. Here, for example,the antennas 201 d, 201 d′, 201 d″, and 201 d′″ may be configured to“share” a PIM detection module.

Exemplary embodiments of the communications system 214 may operate inmultiple bands (e.g., two or more frequency bands). In variousembodiments, signals in a certain frequency (or range of frequencies)may be transmitted in certain polarization(s) and other signals inanother frequency (or range of frequencies) may be transmitted indifferent polarization(s), where the signals at different frequenciesmay interact (or mix) with one another when various techniques describedherein are implemented. This can involve, for example, polarizationadjusting and/or phase shifting/delaying, where one or more component(s)of the antennas 201 d, 201 d′, 201 d″, and 201 d′″, such as radiatingelements, structural portions of radiating elements (e.g., feed port(s),ground plane(s), and/or the like), etc. are adjusted and/or signalsassociated with radiating elements are manipulated/processed. Forinstance, adjustment(s) can be performed via physical/electronicrotation/shifting of the radiating elements (or signals associatedtherewith) in certain columns of one or more of the antennas 201 d, 201d′, 201 d″, and 201 d′″ and/or between antennas that operate/reacttogether, resulting in interference/PIM being picked up by someradiating elements of the communications system 214 and not by otherradiating elements of the communications system 214. Polarizationadjusting and/or phase shifting/delaying can be generally applied or canbe applied for the particular frequencies (or ranges of frequencies)that interact with one another. In various embodiments, theinterference/PIM detection control device 214 d may detectinterference/PIM (e.g., received by the radiating elements and/or by anymonitoring elements included in the antennas) over lines 214 y, and mayprovide data/controls via lines 214 z to the RF-based interference/PIMcanceller 214 f and/or the baseband-based interference/PIM canceller 214b to enable such polarization adjusting and/or phase shifting/delayingby the RF-based interference/PIM canceller 214 f and/or thebaseband-based interference/PIM canceller 214 b. For example, theRF-based interference/PIM canceller 214 f and/or the baseband-basedinterference/PIM canceller 214 b may provide feedback that effectspolarization adjusting and/or phase shifting/delaying for selectradiating elements of select antennas—e.g., for the uplink and/or thedownlink. In certain embodiments, the feedback (which may, for example,be based on, or include, information from collected near-field,intermediate-field, and/or far field energy) may cause radiatingelements/antennas to be remotely tilted (e.g., down or up) and/or emitbeams in certain directions, such as the azimuth direction, etc. In oneor more embodiments, one or more of the antennas 201 d, 201 d′, 201 d″,and 201 d′″ may be configured to adjust signal transmission andreception based on instructions/communications with cancellationsystems/devices included in, or associated with, the radio 214 r, thebaseband processing unit, as well as other system(s) positioned on aCPRI link, an eCPRI link, and/or the like.

In various embodiments, and as shown in FIG. 2N, some or all of theantennas 201 d, 201 d′, 201 d″, and 201 d′″ may (e.g., optionally)include an interference/PIM cancellation block (e.g., interference/PIMcancellation blocks 214 c, 214 c′, 214 c″, and 214 c′″) integratedtherein and configured to provide mitigation or cancellation ofundesired interference/PIM signals. In some of these embodiments, theinterference/PIM detection control device 214 d may providedata/controls to one of more of these interference/PIM cancellationblocks (e.g., similar to that described above with respect to FIG. 2C)to facilitate activation of certain interference/PIMmitigation/cancellation measures (e.g., polarization adjusting and/orphase shifting/delaying via electronic/RF processing of signalsassociated with radiating elements, controlling of physical movements ofradiating elements and/or structural portions thereof, such as byphysically rotating radiating elements, shifting radiating elements,etc., as described herein). In one or more embodiments, aninterference/PIM cancellation block may include some or all of thefunctionalities of the RF-based interference/PIM canceller 214 f and/orthe baseband-based interference/PIM canceller 214 b, in which case oneor more of the RF-based interference/PIM canceller 214 f and/or thebaseband-based interference/PIM canceller 214 b may or may not beincluded or needed. In certain embodiments, an interference/PIMcancellation block may include some or all of the functionalities of theinterference/PIM detection control device 214 d, in which case theinterference/PIM detection control device 214 d may or may not beincluded or needed. In some embodiments, the interference/PIM detectioncontrol device 214 d may be integrated in the baseband unit, the radio214 r, and/or one or more of the antennas 201 d, 201 d′, 201 d″, and 201d′″.

In this way, even in multi-antenna communications systems (wherepre-coding is used to map modulation symbols onto the different antennasto achieve the best possible data reception at the receiver, and wherethe type of pre-coding may depend on the multi-antenna techniqueemployed as well as on the numbers of layers/antenna ports), variousembodiments described herein relating to polarization adjusting and/orphase shifting/delaying can be applied to improve overall systemperformance and coverage.

Certain implementations are provided herein using CoordinatedMulti-Point (CoMP) transmission/reception. This method is considered by3GPP as a tool to improve coverage, cell-edge throughput, and/orspectral efficiency. Depending on the location of a UE, the UE may beable to receive signals from multiple cell sites and the UE'stransmissions may be received at multiple cell sites regardless of thesystem load. If the transmissions from the multiple cell sites arecoordinated for the downlink, the performance can be significantlyincreased. This coordination can be simple, as in the techniques thatfocus on interference or PIM avoidance, or more complex, as in the casewhere the same data is transmitted from multiple cell sites. Inexemplary embodiments, for the uplink, various polarizationadjusting-based and/or phase shifting/delaying-based interference/PIMcancellation techniques described herein (e.g., with an emphasis on thenear field and the intermediate field) can be employed to take advantageof reception at multiple cell sites so as to significantly improve thelink performance.

Certain implementations enhance the requirement reference points atwhich core RF requirements are specified based on the 3GPP. The two mainapproaches used today include defining the requirements at the boundaryof the transceiver and defining the requirements at the far field of theantenna. Exemplary embodiments enable incorporation of additionalrequirements at the intermediate field and the near field of the antennaas well. Downlink MIMO Rel-12 features two CSI enhancements: 4TxPrecoding Matrix Index (PMI) feedback codebook enhancement and aperiodicfeedback Physical Uplink Shared Channel (PUSCH) mode 3-2. The CSIenhancements enable the eNB to complete delivery of data packets earlierthan with legacy CSI feedback, thus improving spectral efficiency. TheRel-12 4Tx codebook enhancement mainly targets cross-polarized antennasand, thus, reuse of the 8Tx dual codebook structure. In addition to theenhanced codebook, a new aperiodic CSI feedback PUSCH mode 3-2 isintroduced in Rel-12 with increased CSI accuracy, since it provides bothsub-band Channel Quality Indication (CQI) and sub-band performancemanagement (PM). The addition of PIM and interference parameters (e.g.,relating to various embodiments described herein, such as those thatimplement polarization adjusting and/or phase shifting/delaying) canfurther enhance the codebook.

Dynamic spectrum sharing (DSS) is a technique where LTE spectrumallocation is dynamically shared between 5G and LTE users. Depending onthe load and traffic demand from both technologies, the base stationdynamically changes the spectrum allocation to use more of the spectrumfor 5G or LTE. As a result, the split between LTE and 5G New Radio (NR)in the spectrum changes over time. DSS is especially appealing tooperators given that its rollout is possible through a software upgradeon existing base station hardware. The 3GPP only provides guidance onhow to configure systems to enable efficient spectrum sharing forstandalone (SA) and non-standalone (NSA) deployments. In exemplaryembodiments, antenna(s) can be controlled to optimize for both 4G/LTEand 5G services by reducing PIM and interference generated from the4G/LTE and 5G requirements so as to enable smooth/seamless DSSoperation.

In TDD, time, rather than frequency, is used to separate thetransmission and reception of signals, and thus a single frequency isassigned to a UE for both the uplink and the downlink. In TDD, two timeslots—one for the uplink and one for the downlink may be assigned toeach UE, with a short data burst in each direction. FIG. 2P is a blockdiagram illustrating an example time frame 216 in a TDD communicationssystem in accordance with various aspects described herein. In variousembodiments, one or more of the antennas described herein (e.g., theantenna 201 of FIG. 2A, the antenna 201 a of FIG. 2C, the antenna 201 bof FIG. 2E, etc.) can be employed in the TDD communications system andoperated in a frequency F1. As depicted in FIG. 2P, the TDD time frame216 may include a time slot 216 a for downlink operations, a time slot216 b for uplink operations, a time slot 216 c for downlink operations,and so on. A guard time/band 216 t between transmit and receive streamsmay generally be needed in TDD. Time split between the forward andreverse channels is sufficiently small that the transmission andreception appear to be simultaneous and continuous to users. The guardtime in TDD is intended as a time allowance for round-trip propagationdelay. This time interval may need to be sufficiently long in order toprevent the transmit and receive signals from clashing. TDD is thusgenerally employed where the distance between the transmitter andreceiver is generally small; otherwise, the channel efficiency may dropand the time guard may need to be rather long.

Since TDD typically permits a higher number of time slots in favor ofone direction of transmission over the other (e.g., usually in favor ofthe downlink), various techniques described herein for polarizationadjusting may be applied to the uplink and/or downlink in a TDDcommunications system in order to reduce or eliminate the guard band. Inexemplary embodiments, for example, techniques described above withrespect to FIGS. 2C, 2E, 2F, 2M, etc. can be employed in a TDD system(e.g., as an additional way) to separate the downlink and the uplink.Here, the downlink and the uplink may be deployed in different (e.g.,orthogonal) polarizations, P1 and P2, respectively. In exemplaryembodiments, the polarization of the uplink can be adjusted relative tothe polarization of the downlink, or vice versa, such that the uplinkpolarization P1 and the downlink polarization P2 are different from oneanother.

For instance, in cases where one or more MIMO antennas that provideparallel transmissions are employed in a TDD system, polarizationadjusting may be applied for some or all of the radiating elementsutilized during downlink operations such that the polarization thereofis in the polarization P1, and may be similarly applied for some or allof the radiating elements utilized during uplink operations such thatthe polarization thereof is in the polarization P2. Doing so creates anadditional dimension of separation that permits a smaller guard band tobe used, which can provide improved network speeds. In extreme cases,guard bands can even be eliminated, where downlink and uplinktransmissions may overlap or coexist without interference by virtue ofthe use of different, orthogonal polarizations P1 and P2.

TDD systems may be deployed in frequency bands that are about 2.5 GHzand higher in order to address guard band delay constraints. However, aTDD system may coexist, or otherwise have overlapping operative ranges,with FDD systems (e.g., in other regions, such as nearby countries) atthe same frequency, which can result in direct interference. In othercases, such FDD systems may operate at lower frequencies, but signalsfrom those FDD systems can mix and generate PIM in the TDD band(s),which can negatively impact the uplink in the TDD system. In exemplaryembodiments, various techniques described herein for polarizationadjusting may be applied to the uplink in a TDD communications system inorder to address any direct interference with FDD system signals and/orany PIM generated by mixing of FDD system signals. In exemplaryembodiments, techniques described above with regard to processing ofsignals or adjustment(s) for component(s) of an antenna system (e.g., asdescribed above with respect to FIGS. 2C, 2E, 2M, etc.) can be employedin the TDD system to separate the TDD uplink from FDD system signals.Here, the TDD uplink may be deployed in particular polarization(s) thatenable the TDD uplink to avoid receiving signals from the FDD systemsand/or any PIM generated by mixing of FDD system signals.

FDD operates the uplink and the downlink in two different frequencies(e.g., frequency F_(a) in the uplink and Fb in the downlink), whichenables simultaneous transmit and receive. Generally, physical duplexersmay be employed on both the transmit and receive of an FDD-based antennasystem to ensure that residual frequency transmissions in the uplink donot overlap or leak into the downlink, and vice versa. Because massiveMIMO involves antennas with numerous radiating elements, it can bechallenging to implement massive MIMO in FDD since it would require alarge number of duplexers to be employed on both the transmit andreceive (e.g., a duplexer on the transmit and a duplexer on the receivefor each radiating element of the antenna). As duplexers generallyinclude multiple stages, where frequency separation is a function of thenumber of stages, incorporation and management of all of these devicesfor optimal frequency separation can be challenging.

Various techniques described herein for polarization adjusting may beapplied to the uplink and/or the downlink in an FDD communicationssystem in order to reduce or eliminate the need for duplexers (e.g., byrelaxing or loosening duplexer requirements). FIG. 2Q is a block diagramillustrating an example FDD communications system 217 in accordance withvarious aspects described herein. In exemplary embodiments, techniquesdescribed above with respect to polarization adjusting, such as thoseinvolving processing of signals or adjustment(s) for component(s) of anantenna system (e.g., as described above with respect to FIGS. 2C, 2E,2M, etc.) can be employed in the FDD communications system 217 (e.g., asan additional way) to separate the uplink and downlink frequencies F_(a)and Fb. Here, the uplink and the downlink may be deployed in different(e.g., orthogonal) polarizations, P_(a) and P_(b), respectively. Doingso creates an additional dimension of separation that permits the use offewer or less sophisticated duplexers (e.g., duplexers with fewerstages), since signal gain (in dB) that might otherwise be offeredthrough the use of more duplexer stages can instead be provided viapolarization adjusting. This can advantageously enable massive MIMOimplementations in FDD. In extreme cases, duplexers can even beeliminated altogether by virtue of the use of different, orthogonalpolarizations P_(a) and P_(b).

Based on parameters of detected interference/PIM and/or based oncondition(s) relating to TDD/FDD communications, there may be optimal ordesired directions or polarizations for receiving communications (theuplink) and transmitting communications (the downlink). In variousembodiments, polarization adjusting can be effected by performing one ormore techniques described herein, such as by physically rotating orelectronically rotating one or both elements of anorthogonally-polarized element pair and/or by altering one or morestructural properties of an orthogonally-polarized element pair, suchthat an uplink polarization is different from (e.g., is orthogonal to) adownlink polarization.

In a case where physical rotation is employed, for a givenorthogonally-polarized element pair, one element of theorthogonally-polarized element pair may need to be utilized for theuplink and the other element of the orthogonally-polarized element pairmay need to be utilized for the downlink. Referring to FIG. 2M merely asan example, dipole element 213 u can be operated in the uplink (or,alternatively, the downlink) and dipole element 213 v can be operated inthe downlink (or, alternatively, the uplink). Here, polarizationadjusting can involve causing dipole element 213 u to physically rotateby a certain angle in a certain direction, causing dipole element 213 vto physically rotate by a certain angle in a certain direction, or both,which can result in the uplink and downlink polarizations beingdifferent from one another. Where crossed-dipole radiating element 213u, 213 v is included as one of the radiating elements of an antenna,such as, for example, the antenna 201 b of FIG. 2E or the like,polarization adjusting via physical rotation can, for one or morecolumns of radiating elements, be effected such that one or more dipoleelements (e.g., each dipole element) in one of the orientations (e.g.,the dipole elements oriented in −45 degrees) is rotated by a certainangle in a certain direction, one or more dipole elements (e.g., eachdipole element) in another physical orientation (e.g., the dipoleelements oriented in +45 degrees) is rotated by a certain angle in acertain direction, or both.

In a case where rotation of radiating elements is appliedelectronically, for a given orthogonally-polarized element pair, eachelement of the orthogonally-polarized element pair may be operated inboth the uplink and the downlink. Referring to FIG. 2M merely as anexample, dipole element 213 u can be operated in both the uplink and thedownlink, and dipole element 213 v can be operated in both the uplinkand the downlink. Here, polarization adjusting can involve gain mixing(e.g., similar to that described above with respect to FIG. 2M) thatresults in the uplink polarization and the downlink polarization for aparticular dipole element being different from (e.g., orthogonal to) oneanother. This can be achieved, for example: by determining andapplying/feeding a signal for an uplink of dipole element 213 u (e.g., asignal s₁′(t)-uplink) based on some angle, such as angle 213 w; bydetermining and applying/feeding a signal for a downlink of dipoleelement 213 u (e.g., a signal s₁′(t)-downlink) based on a differentangle or a 0 degree angle; by determining and applying/feeding a signalfor an uplink of dipole element 213 v (e.g., a signal s₂′(t)-uplink)based on some angle; by determining and applying/feeding a signal for adownlink of dipole element 213 v (e.g., a signal s₂′(t)-downlink) basedon a different angle or a 0 degree angle; or the like. In other words,any combination of zero and non-zero angles can be applied amongst theuplinks and downlinks for a given orthogonally-polarized element pair toarrive at uplink/downlink polarization differentiation. Wherecrossed-dipole radiating element 213 u, 213 v is included as one of theradiating elements of an antenna (e.g., a MIMO antenna), such as, forexample, the antenna 201 b of FIG. 2E or the like, polarizationadjusting via electronic-based rotation can, for one or more columns ofradiating elements, be effected in a similar manner such that uplink anddownlink polarizations are different.

It is to be appreciated and understood that different configurations canbe employed to provide physical rotation and/or electronic rotation ofradiating elements and/or altering of one or more structural propertiesof radiating elements. As an example, in various embodiments, an antennasystem may include one port for elements of a set (e.g., a column) oforthogonally-polarized element pairs oriented in a first manner (e.g.,dipole elements oriented in −45 degrees), another port for elements ofthe set (e.g., column) of orthogonally-polarized element pairs orientedin a second manner (e.g., dipole elements oriented in +45 degrees), andsimilar ports for one or more other columns of orthogonally-polarizedelement pairs (if any). In this example, polarization adjusting (suchas, for example, to achieve different uplink and downlink polarizations)can be effected electronically by determining and applying/feeding arespective signal (including, for example, respective uplink anddownlink signals) to each of the ports.

As another example, in various embodiments, an antenna system mayinclude an individual port for each element of an orthogonally-polarizedelement pair (e.g., 16 ports for 8 orthogonally-polarized elementpairs). In this example, polarization adjusting (such as, for example,to achieve different uplink and downlink polarizations) can be effectedelectronically by determining and applying/feeding a respective signal(including, for example, respective uplink and downlink signals), via arespective port, for each element of the orthogonally-polarized elementpairs (e.g., 32 uplink/downlink signals for 16 elements of 8orthogonally-polarized element pairs).

It is to be appreciated and understood that polarization adjusting viaelectronic rotation can be effected or controlled by a BBU, a radio, ora system integrated in an antenna. In one or more embodiments, anantenna may include a respective device or circuitry for eachorthogonally-polarized element pair or for each element of eachorthogonally-polarized element pair. The device or circuitry mayinclude, for example, polarization shifter component(s) or device(s)(e.g., analog polarization rotator(s)) operatively coupled to eachorthogonally-polarized element pair or to each element of eachorthogonally-polarized element pair. In various embodiments, therespective device or circuitry may obtain signals (e.g., s₁(t), s₁′ (t),s₂(t), or the like, etc.) determined or generated by a BBU, a radio, orother system, and may apply/feed such signals to the respectiveorthogonally-polarized element pairs or to the respective elements ofthe orthogonally-polarized element pairs. In this way, appropriateangle(s) of rotation (if applicable) can be applied for selectorthogonally-polarized element pairs or select elements oforthogonally-polarized element pairs, such that even elements that arephysically oriented in the same manner (e.g., physically oriented at −45degrees) can be selectively electronically polarized at different anglesas desired.

In various embodiments, an antenna may include a respective device orcircuitry and/or associated motor or set of motors for eachorthogonally-polarized element pair or for each element of eachorthogonally-polarized element pair, which enables polarizationadjusting via physical rotation(s).

In one or more embodiments, one or more AISG interfaces or control linescan be leveraged to provide command(s) relating to polarizationadjusting, where the commands can, for example, be embedded in a controlport (e.g., operating at a different frequency from signal frequencies)and used by the above-described circuitry or devices to apply/feedappropriate signals to respective orthogonally-polarized element pairsor to respective elements of the orthogonally-polarized element pairs orto cause physical rotation of respective orthogonally-polarized elementpairs or respective elements of the orthogonally-polarized elementpairs.

As described above with respect to FIG. 2F, phase shifting/delaying canbe implemented via physical displacement of radiating element(s). In oneor more embodiments, and similar to embodiments relating to physicalrotation of radiating elements, an antenna may include a respectivedevice or circuitry and/or associated motor or set of motors for eachorthogonally-polarized element pair or for each element of eachorthogonally-polarized element pair, which enables polarizationadjusting via physical displacement/shifting of radiating elements. Itis to be appreciated and understood that phase shifting/delaying can beadditionally, or alternatively, effected electronically. For example, invarious embodiments, an antenna may include a respective phaseshift/delay device or circuitry, for each orthogonally-polarized elementpair or for each element of each orthogonally-polarized element pair,that enables introduction of phase delays for signals associated withselect elements or element pairs.

In certain embodiments, phase adjusting can be employed in acommunications system, such as a TDD or FDD communications system, toarrive at a difference between the uplink and the downlink (e.g.,similar to polarization differences provided via polarizationadjusting). In these embodiments, phase shifts/delays can be providedelectronically or physically in antenna configurations and manner(s)similar to those described above with respect to electronic/physicalrotation of orthogonally-polarized element pairs or individual elementsof orthogonally-polarized element pairs. As with embodiments involvingpolarization adjusting via physical rotation, in a case where phaseadjusting is implemented via physical displacement of radiatingelements, for a given orthogonally-polarized element pair in which adifference between the uplink and the downlink is desired, one elementof the orthogonally-polarized element pair may need to be utilized forthe uplink and the other element of the orthogonally-polarized elementpair may need to be utilized for the downlink. Further, as withembodiments involving polarization adjusting via electronic rotation ofradiating elements, in a case where phase adjusting is implementedelectronically, for a given an orthogonally-polarized element pair, eachelement of the orthogonally-polarized element pair may be operated inboth the uplink and the downlink.

It is to be appreciated and understood that the quantity and arrangementof communications systems, antennas, UEs, radiating elements, monitoringelements, outputs, radios, interference/PIM cancellation systems,interference/PIM detection control devices, AISG interfaces, motors, RFbaseband interference/PIM cancellers, and/or baseband-basedinterference/PIM cancellers shown in FIGS. 2A, 2C, 2D, 2E, 2F, 2G, 2M,2N, 2P, and/or 2Q are provided as an example. In practice, there may beadditional communications systems, antennas, UEs, radiating elements,monitoring elements, outputs, radios, interference/PIM cancellationsystems, interference/PIM detection control devices, AISG interfaces,motors, RF baseband interference/PIM cancellers, and/or baseband-basedinterference/PIM cancellers than those shown in FIGS. 2A, 2C, 2D, 2E,2F, 2G, 2M, 2N, 2P, and/or 2Q. For example, various embodiments mayinclude more or fewer communications systems, antennas, UEs, radiatingelements, monitoring elements, outputs, radios, interference/PIMcancellation systems, interference/PIM detection control devices, AISGinterfaces, motors, RF baseband interference/PIM cancellers, and/orbaseband-based interference/PIM cancellers. Furthermore, two or morecommunications systems, antennas, UEs, radiating elements, monitoringelements, outputs, radios, interference/PIM cancellation systems,interference/PIM detection control devices, AISG interfaces, motors, RFbaseband interference/PIM cancellers, or baseband-based interference/PIMcancellers shown in FIGS. 2A, 2C, 2D, 2E, 2F, 2G, 2M, 2N, 2P, and/or 2Qmay be implemented within a single communications system, antenna, UE,radiating element, monitoring element, output, radio, interference/PIMcancellation system, interference/PIM detection control device, AISGinterface, motor, RF baseband interference/PIM canceller, orbaseband-based interference/PIM canceller shown in FIGS. 2A, 2C, 2D, 2E,2F, 2G, 2M, 2N, 2P, and/or 2Q or a single communications system,antenna, UE, radiating element, monitoring element, output, radio,interference/PIM cancellation system, interference/PIM detection controldevice, AISG interface, motor, RF baseband interference/PIM canceller,or baseband-based interference/PIM canceller shown in FIGS. 2A, 2C, 2D,2E, 2F, 2G, 2M, 2N, 2P, and/or 2Q may be implemented as multiple,distributed communications systems, antennas, UEs, radiating elements,monitoring elements, outputs, radios, interference/PIM cancellationsystems, interference/PIM detection control devices, AISG interfaces,motors, RF baseband interference/PIM cancellers, or baseband-basedinterference/PIM cancellers. Additionally, or alternatively, a set ofcommunications systems, antennas, UEs, radiating elements, monitoringelements, outputs, radios, interference/PIM cancellation systems,interference/PIM detection control devices, AISG interfaces, motors, RFbaseband interference/PIM cancellers, and/or baseband-basedinterference/PIM cancellers (e.g., one or more communications systems,antennas, UEs, radiating elements, monitoring elements, outputs, radios,interference/PIM cancellation systems, interference/PIM detectioncontrol devices, AISG interfaces, motors, RF baseband interference/PIMcancellers, and/or baseband-based interference/PIM cancellers) mayperform one or more functions described as being performed by anotherset of communications systems, antennas, UEs, radiating elements,monitoring elements, outputs, radios, interference/PIM cancellationsystems, interference/PIM detection control devices, AISG interfaces,motors, RF baseband interference/PIM cancellers, and/or baseband-basedinterference/PIM cancellers.

FIG. 2R depicts an illustrative embodiment of a method 220 in accordancewith various aspects described herein. In some embodiments, one or moreprocess blocks of FIG. 2R can be performed by an interference/PIMcancellation system, such as one or more of the interference/PIMcancellation systems described herein. In certain embodiments, one ormore process blocks of FIG. 2R may be performed by another device or agroup of devices separate from or including the interference/PIMcancellation system, such as a radio (e.g., an RRH), a baseband unit(BBU), an antenna or antenna system, an interference/PIM detectioncontrol device, and/or an AISG interface.

At 222, the method can include receiving, via an antenna, acommunication signal generated by a communication device. For example,step 222 can be performed in a manner similar to that describedelsewhere herein.

At 224, the method can include detecting interference in thecommunication signal, wherein the interference is generated by one ormore interference sources, wherein the interference is detected bymonitoring a near field region of the antenna, an intermediate fieldregion of the antenna, a far field region of the antenna, or anycombinations thereof, wherein the monitoring excludes monitoring onlythe far field region of the antenna. For example, step 224 can beperformed in a manner similar to that described elsewhere herein.

In some implementations of these embodiments, the intermediate fieldregion comprises a region that spans a portion of the near field regionof the antenna and a portion of the far field region of the antenna.

In some implementations of these embodiments, the method furthercomprises identifying an antenna resource for mitigating theinterference, and performing by the antenna resource conditioning on thecommunication signal to reduce the interference.

In some implementations of these embodiments, the antenna comprises aplurality of radiating elements, wherein the antenna is configured tooperate the plurality of radiating elements in bands that mix andinterfere together. In some implementations of these embodiments, theinterference detected includes mixing and interference of the bands,wherein the interference detected comprises passive intermodulation(PIM) interference.

In some implementations of these embodiments, the interference comprisesintercell interference.

In some implementations of these embodiments, the interference isgenerated from dynamic spectrum sharing between transmitters.

In some implementations of these embodiments, the interference comprisesleakage interference generated by another base station.

In some implementations of these embodiments, a polarization of theinterference enables detection of the interference. In someimplementations of these embodiments, the polarization of theinterference is detectable separately from other signals received by theantenna.

In some implementations of these embodiments, the antenna is integratedwith a remote radio head.

In some implementations of these embodiments, the antenna operates in acommunication system utilizing time division multiple access.

In some implementations of these embodiments, the antenna operates in acommunication system utilizing frequency division multiple access.

In some implementations of these embodiments, a signaling protocol usedby one or more transmitters unassociated with the antenna comprises anorthogonal frequency-division multiple access protocol. In someimplementations of these embodiments, the interference is furtherdetected by detecting the signaling protocol used by the one or moretransmitters.

While for purposes of simplicity of explanation, the respectiveprocesses are shown and described as a series of blocks in FIG. 2R, itis to be understood and appreciated that the claimed subject matter isnot limited by the order of the blocks, as some blocks may occur indifferent orders and/or concurrently with other blocks from what isdepicted and described herein. Moreover, not all illustrated blocks maybe required to implement the methods described herein.

In various embodiments, a device comprises a circuit coupled to anantenna. The circuit facilitates operations, including receiving, viathe antenna, a signal generated by a communication device, and detectinginterference in the signal, wherein the interference is generated by oneor more sources, wherein the interference is detected by monitoring anear field region of the antenna, an intermediate field of the antenna,a far field region of the antenna, or any combinations thereof, whereinthe monitoring excludes monitoring only the far field region of theantenna.

In some implementations of these embodiments, the operations furtherinclude identifying a resource for mitigating the interference.

In some implementations of these embodiments, the circuit is configuredto detect a polarization of the interference.

In various embodiments, a non-transitory machine-readable mediumcomprises executable instructions that, when executed by a processingsystem including a processor, facilitate performance of operations. Theoperations comprise receiving, via an antenna, a communication signalgenerated by a communication device, and detecting interference in thecommunication signal, wherein the interference is generated by one ormore interference sources, wherein the interference is detected bymonitoring a near field region of the antenna, an intermediate fieldregion of the antenna, or both with or without monitoring a far fieldregion of the antenna.

In some implementations of these embodiments, the operations furthercomprise controlling, by a remote radio unit, the antenna to perform oneor more actions for mitigating or cancelling the interference.

FIG. 2S depicts an illustrative embodiment of a method 230 in accordancewith various aspects described herein. In some embodiments, one or moreprocess blocks of FIG. 2S can be performed by an interference/PIMcancellation system, such as one or more of the interference/PIMcancellation systems described herein. In certain embodiments, one ormore process blocks of FIG. 2S may be performed by another device or agroup of devices separate from or including the interference/PIMcancellation system, such as a radio (e.g., an RRH), a baseband unit(BBU), an antenna or antenna system, an interference/PIM detectioncontrol device, and/or an AISG interface. In one or more embodiments,the method can include operations. For example, a device may comprise aprocessing system including a processor and associated with acommunications system, and a memory that stores executable instructionsthat, when executed by the processing system, facilitate performance ofsuch operations.

At 232, the method can include obtaining data regarding passiveintermodulation (PIM) detected in a received communication signal. Forexample, step 232 can be performed in a manner similar to that describedelsewhere herein.

At 234, the method can include performing polarization adjusting for acommunications system such that an impact of the PIM on thecommunications system is minimized. For example, step 234 can beperformed in a manner similar to that described elsewhere herein.

In some implementations of these embodiments, the PIM originates in anear field region of an antenna system of the communications system oran intermediate field region of the antenna system that spans a portionof the near field region and a portion of a far field region of theantenna system.

In some implementations of these embodiments, the performing thepolarization adjusting results in no impact to a far field region of anantenna system of the communications system, as compared to a case wherethe polarization adjusting is not performed.

In some implementations of these embodiments, the performing thepolarization adjusting comprises rotating one or more radiating elementsof an antenna system of the communications system.

In some implementations of these embodiments, the performing thepolarization adjusting comprises performing electronic adjustments forone or more radiating elements of an antenna system of thecommunications system.

While for purposes of simplicity of explanation, the respectiveprocesses are shown and described as a series of blocks in FIG. 2S, itis to be understood and appreciated that the claimed subject matter isnot limited by the order of the blocks, as some blocks may occur indifferent orders and/or concurrently with other blocks from what isdepicted and described herein. Moreover, not all illustrated blocks maybe required to implement the methods described herein.

In various embodiments, a method comprises obtaining data regardingpassive intermodulation (PIM) originating from one or more interferencesources, and mitigating, by an adjusting mechanism associated with acommunications system, the PIM by performing polarization adjusting forthe communications system.

In some implementations of these embodiments, the PIM originates in anear field region of an antenna system of the communications system oran intermediate field region of the antenna system that spans a portionof the near field region and a portion of a far field region of theantenna system.

In some implementations of these embodiments, the performing thepolarization adjusting results in no impact to a far field region of anantenna system of the communications system, as compared to a case wherethe polarization adjusting is not performed.

In some implementations of these embodiments, the performing thepolarization adjusting comprises rotating one or more radiating elementsof an antenna system of the communications system.

In some implementations of these embodiments, the performing thepolarization adjusting comprises performing electronic adjustments forone or more radiating elements of an antenna system of thecommunications system.

In some implementations of these embodiments, the performing thepolarization adjusting involves one or more adjustments for one or moreorthogonally-polarized element pairs of an antenna system of thecommunications system.

In some implementations of these embodiments, the communications systemcomprises a multiple-input-multiple-output (MIMO) antenna.

In some implementations of these embodiments, the polarization adjustingis performed by a remote radio unit.

In some implementations of these embodiments, the polarization adjustinginvolves controlling one or more motors.

In some implementations of these embodiments, the obtaining is performedby a processing system including a processor, wherein the adjustingmechanism is included in or comprises the processing system.

In various embodiments, a non-transitory machine-readable mediumcomprises executable instructions that, when executed by a processingsystem including a processor and associated with a communicationssystem, facilitate performance of operations. The operations comprisereceiving data regarding interference present in a receivedcommunication signal, and performing polarization adjusting for thecommunications system such that the interference is mitigated.

In some implementations of these embodiments, the interferenceoriginates in a near field region of an antenna system of thecommunications system or an intermediate field region of the antennasystem that spans a portion of the near field region and a portion of afar field region of the antenna system.

In some implementations of these embodiments, the performing thepolarization adjusting results in no impact to a far field region of anantenna system of the communications system, as compared to a case wherethe polarization adjusting is not performed.

In some implementations of these embodiments, the performing thepolarization adjusting involves one or more adjustments for one or moreorthogonally-polarized element pairs of an antenna system of thecommunications system.

In some implementations of these embodiments, the communications systemcomprises a multiple-input-multiple-output (MIMO) antenna.

FIG. 2T depicts an illustrative embodiment of a method 240 in accordancewith various aspects described herein. In some embodiments, one or moreprocess blocks of FIG. 2T can be performed by an interference/PIMcancellation system, such as one or more of the interference/PIMcancellation systems described herein. In certain embodiments, one ormore process blocks of FIG. 2T may be performed by another device or agroup of devices separate from or including the interference/PIMcancellation system, such as a radio (e.g., an RRH), a baseband unit(BBU), an antenna or antenna system, an interference/PIM detectioncontrol device, and/or an AISG interface. In one or more embodiments,the method can include operations. For example, a device may comprise aprocessing system including a processor and associated with an antennasystem, and a memory that stores executable instructions that, whenexecuted by the processing system, facilitate performance of suchoperations.

At 242, the method can include obtaining data regarding interferencedetected in a received communication signal. For example, step 242 canbe performed in a manner similar to that described elsewhere herein.

At 244, the method can include performing polarization adjusting byrotating one or more radiating elements of an antenna system such thatan impact of the interference on the antenna system is minimized. Forexample, step 244 can be performed in a manner similar to that describedelsewhere herein.

In some implementations of these embodiments, the interferenceoriginates in a near field region of the antenna system or anintermediate field region of the antenna system that spans a portion ofthe near field region and a portion of a far field region of the antennasystem.

In some implementations of these embodiments, the performing thepolarization adjusting results in no impact to a far field region of theantenna system, as compared to a case where the polarization adjustingis not performed.

In some implementations of these embodiments, the interference comprisespassive intermodulation (PIM).

In some implementations of these embodiments, the polarization adjustingcomprises rotating a subset of the radiating elements of the antennasystem.

While for purposes of simplicity of explanation, the respectiveprocesses are shown and described as a series of blocks in FIG. 2T, itis to be understood and appreciated that the claimed subject matter isnot limited by the order of the blocks, as some blocks may occur indifferent orders and/or concurrently with other blocks from what isdepicted and described herein. Moreover, not all illustrated blocks maybe required to implement the methods described herein.

In various embodiments, a method comprises obtaining data regardinginterference originating from one or more interference sources, andmitigating, by an adjusting mechanism associated with an antenna system,the interference by performing polarization adjusting via rotation ofradiating elements of the antenna system.

In some implementations of these embodiments, the interferenceoriginates in a near field region of the antenna system or anintermediate field region of the antenna system that spans a portion ofthe near field region and a portion of a far field region of the antennasystem.

In some implementations of these embodiments, the performing thepolarization adjusting results in no impact to a far field region of theantenna system, as compared to a case where the polarization adjustingis not performed.

In some implementations of these embodiments, the interference comprisespassive intermodulation (PIM).

In some implementations of these embodiments, the radiating elementscomprise orthogonally-polarized element pairs.

In some implementations of these embodiments, the antenna systemcomprises a plurality of antennas, wherein the radiating elements areincluded in one antenna of the plurality of antennas.

In some implementations of these embodiments, the antenna systemcomprises a single antenna having a plurality of radiating elements,wherein the radiating elements comprise a subset of the plurality ofradiating elements.

In some implementations of these embodiments, the polarization adjustingcomprises rotating a first set of radiating elements by a first angle ofrotation and a second set of radiating elements by a second angle ofrotation.

In some implementations of these embodiments, the polarization adjustingis performed by a remote radio unit.

In some implementations of these embodiments, the polarization adjustinginvolves controlling one or more motors.

In some implementations of these embodiments, the polarization adjustingis performed via one or more Antenna Interface Standards Group(AISG)-based interfaces.

In some implementations of these embodiments, the obtaining is performedby a processing system including a processor, wherein the adjustingmechanism is included in or comprises the processing system.

In various embodiments, a non-transitory machine-readable mediumcomprises executable instructions that, when executed by a processingsystem including a processor and associated with an antenna system,facilitate performance of operations. The operations comprise receivingdata regarding interference present in a received communication signal,and performing polarization adjusting by causing one or more radiatingelements of the antenna system to be rotated such that the interferenceis mitigated.

In some implementations of these embodiments, the performing thepolarization adjusting results in no impact to a far field region of theantenna system, as compared to a case where the polarization adjustingis not performed.

In some implementations of these embodiments, the polarization adjustingcomprises rotating a subset of the radiating elements of the antennasystem.

FIG. 2U depicts an illustrative embodiment of a method 250 in accordancewith various aspects described herein. In some embodiments, one or moreprocess blocks of FIG. 2U can be performed by an interference/PIMcancellation system, such as one or more of the interference/PIMcancellation systems described herein. In certain embodiments, one ormore process blocks of FIG. 2U may be performed by another device or agroup of devices separate from or including the interference/PIMcancellation system, such as a radio (e.g., an RRH), a baseband unit(BBU), an antenna or antenna system, an interference/PIM detectioncontrol device, and/or an AISG interface. In one or more embodiments,the method can include operations. For example, a device may comprise aprocessing system including a processor and associated with an antennasystem, and a memory that stores executable instructions that, whenexecuted by the processing system, facilitate performance of suchoperations.

At 252, the method can include obtaining data regarding interferencedetected in a received communication signal. For example, step 252 canbe performed in a manner similar to that described elsewhere herein.

At 254, the method can include performing phase adjusting for one ormore radiating elements of an antenna system such that an impact of theinterference on the antenna system is minimized. For example, step 254can be performed in a manner similar to that described elsewhere herein.

In some implementations of these embodiments, the interferenceoriginates in a near field region of the antenna system or anintermediate field region of the antenna system that spans a portion ofthe near field region and a portion of a far field region of the antennasystem.

In some implementations of these embodiments, the performing the phaseadjusting results in no impact to a far field region of the antennasystem, as compared to a case where the phase adjusting is notperformed.

In some implementations of these embodiments, the performing the phaseadjusting comprises physically displacing the one or more radiatingelements along an axis of the antenna system.

In some implementations of these embodiments, the performing the phaseadjusting comprises electronically applying a phase shift or delay toone or more signals associated with the one or more radiating elements.

While for purposes of simplicity of explanation, the respectiveprocesses are shown and described as a series of blocks in FIG. 2U, itis to be understood and appreciated that the claimed subject matter isnot limited by the order of the blocks, as some blocks may occur indifferent orders and/or concurrently with other blocks from what isdepicted and described herein. Moreover, not all illustrated blocks maybe required to implement the methods described herein.

In various embodiments, a method comprises obtaining data regardinginterference originating from one or more interference sources, andmitigating, by an adjusting mechanism associated with an antenna system,the interference by performing phase adjusting of radiating elements ofthe antenna system.

In some implementations of these embodiments, the interferenceoriginates in a near field region of the antenna system or anintermediate field region of the antenna system that spans a portion ofthe near field region and a portion of a far field region of the antennasystem.

In some implementations of these embodiments, the performing the phaseadjusting results in no impact to a far field region of the antennasystem, as compared to a case where the phase adjusting is notperformed.

In some implementations of these embodiments, the interference comprisespassive intermodulation (PIM).

In some implementations of these embodiments, the radiating elementscomprise orthogonally-polarized element pairs.

In some implementations of these embodiments, the antenna systemcomprises a plurality of antennas, wherein the radiating elements areincluded in one antenna of the plurality of antennas.

In some implementations of these embodiments, the antenna systemcomprises a single antenna having a plurality of radiating elements,wherein the radiating elements comprise a subset of the plurality ofradiating elements.

In some implementations of these embodiments, the performing the phaseadjusting comprises physically displacing a subset of the radiatingelements along an axis of the antenna system.

In some implementations of these embodiments, the performing the phaseadjusting comprises electronically applying a phase shift or delay toone or more signals associated with a subset of the radiating elementsof the antenna system.

In some implementations of these embodiments, the performing the phaseadjusting comprises displacing a first set of radiating elements by afirst amount in a first direction and a second set of radiating elementsby a second amount in a second direction opposite the first direction.

In some implementations of these embodiments, the phase adjusting isperformed by a remote radio unit, by controlling one or more motors, ora combination thereof.

In some implementations of these embodiments, the phase adjusting isperformed via one or more Antenna Interface Standards Group (AISG)-basedinterfaces.

In some implementations of these embodiments, the obtaining is performedby a processing system including a processor, wherein the adjustingmechanism is included in or comprises the processing system.

In various embodiments, a non-transitory machine-readable mediumcomprises executable instructions that, when executed by a processingsystem including a processor and associated with an antenna system,facilitate performance of operations. The operations comprise receivingdata regarding interference present in a received communication signal,and performing phase adjusting by causing one or more radiating elementsof the antenna system to be displaced along an axis of the antennasystem such that the interference is mitigated.

In some implementations of these embodiments, the performing the phaseadjusting results in no impact to a far field region of the antennasystem, as compared to a case where the phase adjusting is notperformed.

FIG. 2V depicts an illustrative embodiment of a method 260 in accordancewith various aspects described herein. In some embodiments, one or moreprocess blocks of FIG. 2V can be performed by an interference/PIMcancellation system, such as one or more of the interference/PIMcancellation systems described herein. In certain embodiments, one ormore process blocks of FIG. 2V may be performed by another device or agroup of devices separate from or including the interference/PIMcancellation system, such as a radio (e.g., an RRH), a baseband unit(BBU), an antenna or antenna system, an interference/PIM detectioncontrol device, and/or an AISG interface. In one or more embodiments,the method can include operations. For example, a device may comprise aprocessing system associated with a time-division duplexing (TDD)communications system and including a processor, and a memory thatstores executable instructions that, when executed by the processingsystem, facilitate performance of such operations.

At 262, the method can include performing polarization adjusting for anuplink of a TDD communications system. For example, step 262 can beperformed in a manner similar to that described elsewhere herein.

At 264, the method can include performing polarization adjusting for adownlink of the TDD communications system, wherein a first polarizationof the uplink and a second polarization of the downlink are different.For example, step 264 can be performed in a manner similar to thatdescribed elsewhere herein.

In some implementations of these embodiments, the first polarization isorthogonal to the second polarization.

In some implementations of these embodiments, the TDD communicationssystem comprises a multiple-input-multiple-output (MIMO) antenna.

In some implementations of these embodiments, the TDD communicationssystem comprises an antenna system having a plurality oforthogonally-polarized element pairs.

In some implementations of these embodiments, the TDD communicationssystem comprises an antenna system having a plurality of radiatingelements, wherein the performing the polarization adjusting for theuplink or the performing the polarization adjusting for the downlinkcomprises causing a subset of the plurality of radiating elements torotate.

While for purposes of simplicity of explanation, the respectiveprocesses are shown and described as a series of blocks in FIG. 2V, itis to be understood and appreciated that the claimed subject matter isnot limited by the order of the blocks, as some blocks may occur indifferent orders and/or concurrently with other blocks from what isdepicted and described herein. Moreover, not all illustrated blocks maybe required to implement the methods described herein.

In various embodiments, a non-transitory machine-readable mediumcomprises executable instructions that, when executed by a processingsystem associated with a frequency-division duplexing (FDD)communications system and including a processor, facilitate performanceof operations. The operations comprise performing polarization adjustingfor an uplink of the FDD communications system, and performingpolarization adjusting for a downlink of the FDD communications system,wherein a first polarization of the uplink and a second polarization ofthe downlink are different.

In some implementations of these embodiments, the first polarization isorthogonal to the second polarization.

In some implementations of these embodiments, the FDD communicationssystem employs massive multiple-input-multiple-output (MIMO).

In some implementations of these embodiments, the FDD communicationssystem comprises an antenna system having a plurality oforthogonally-polarized element pairs.

In some implementations of these embodiments, the FDD communicationssystem comprises an antenna system having a plurality of radiatingelements, wherein the performing the polarization adjusting for theuplink or the performing the polarization adjusting for the downlinkcomprises causing a subset of the plurality of radiating elements tobecome physically adjusted, electronically adjusted, or both physicallyand electronically adjusted.

In various embodiments, a method comprises performing, by an adjustingmechanism associated with a communications system, polarizationadjusting for an uplink of the communications system, and performing, bythe adjusting mechanism, polarization adjusting for a downlink of thecommunications system, wherein a first polarization of the uplink and asecond polarization of the downlink are different.

In some implementations of these embodiments, the first polarization isorthogonal to the second polarization.

In some implementations of these embodiments, the communications systemcomprises a TDD communications system.

In some implementations of these embodiments, the communications systemcomprises an FDD communications system. In some implementations of theseembodiments, the FDD communications system employs massivemultiple-input-multiple-output (MIMO).

In some implementations of these embodiments, the communications systemcomprises an antenna system having a plurality of orthogonally-polarizedelement pairs.

In some implementations of these embodiments, the first polarizationbeing different from the second polarization enables uplinktransmissions and downlink transmissions to overlap with one another.

In some implementations of these embodiments, the performing thepolarization adjusting for the uplink or the performing the polarizationadjusting for the downlink enables the uplink to avoid detectinginterference generated by multiple frequency-division duplexing (FDD)communications systems

In some implementations of these embodiments, the performing thepolarization adjusting for the uplink comprises adjusting a polarizationassociated with at least one radiating element of a plurality ofradiating elements of an antenna.

In some implementations of these embodiments, the performing thepolarization adjusting for the downlink comprises adjusting apolarization associated with at least one radiating element of aplurality of radiating elements of an antenna.

FIG. 2W depicts an illustrative embodiment of a method 270 in accordancewith various aspects described herein. In some embodiments, one or moreprocess blocks of FIG. 2W can be performed by an interference/PIMcancellation system, such as one or more of the interference/PIMcancellation systems described herein. In certain embodiments, one ormore process blocks of FIG. 2W may be performed by another device or agroup of devices separate from or including the interference/PIMcancellation system, such as a radio (e.g., an RRH), a baseband unit(BBU), an antenna or antenna system, an interference/PIM detectioncontrol device, and/or an AISG interface.

At 272, the method can include identifying one or more radiatingelements of an antenna system that are to be adjusted based oninterference determined to affect an operation of the antenna system.For example, step 272 can be performed in a manner similar to thatdescribed elsewhere herein.

At 274, the method can include altering one or more properties of theone or more radiating elements to effect polarization adjusting suchthat an impact of the interference on the antenna system is minimized.For example, step 274 can be performed in a manner similar to thatdescribed elsewhere herein.

In some implementations of these embodiments, the interferenceoriginates in a near field region of the antenna system or anintermediate field region of the antenna system that spans a portion ofthe near field region and a portion of a far field region of the antennasystem.

In some implementations of these embodiments, the polarization adjustingresults in no impact to a far field region of the antenna system, ascompared to a case where the polarization adjusting is not performed.

In some implementations of these embodiments, the interference comprisespassive intermodulation (PIM).

In some implementations of these embodiments, the one or more propertiesrelate to physical shape.

In some implementations of these embodiments, the one or more propertiesrelate to physical dimensions.

In some implementations of these embodiments, the one or more propertiesrelate to electrical properties, magnetic properties, or a combinationthereof.

In some implementations of these embodiments, the one or more radiatingelements comprise a subset of the radiating elements of the antennasystem.

In some implementations of these embodiments, the antenna system isassociated with a frequency-division duplexing (FDD) communicationssystem or a time-division duplexing (TDD) communications system.

In some implementations of these embodiments, the antenna systemcomprises a plurality of antennas, wherein the one or more radiatingelements are included in one antenna of the plurality of antennas.

In some implementations of these embodiments, the antenna systemcomprises a single antenna having a plurality of radiating elements,wherein the one or more radiating elements comprise a subset of theplurality of radiating elements.

In some implementations of these embodiments, the antenna systemcomprises a plurality of radiating elements that includes the one ormore radiating elements and other radiating elements, wherein the otherradiating elements have one or more other properties.

While for purposes of simplicity of explanation, the respectiveprocesses are shown and described as a series of blocks in FIG. 2W, itis to be understood and appreciated that the claimed subject matter isnot limited by the order of the blocks, as some blocks may occur indifferent orders and/or concurrently with other blocks from what isdepicted and described herein. Moreover, not all illustrated blocks maybe required to implement the methods described herein.

In various embodiments, a device comprises a processing system includinga processor and associated with an antenna system having a plurality ofradiating elements, and a memory that stores executable instructionsthat, when executed by the processing system, facilitate performance ofoperations. The operations comprise operating the antenna system in acommunications system, and mitigating interference via polarizationadjusting, wherein the polarization adjusting is provided based on oneor more of the plurality of radiating elements of the antenna systembeing adapted to exhibit one or more properties.

In some implementations of these embodiments, the polarization adjustingresults in no impact to a far field region of the antenna system, ascompared to a case where the polarization adjusting is not provided.

In some implementations of these embodiments, the one or more propertiesrelate to physical shape, physical dimensions, or a combination thereof.

In some implementations of these embodiments, the one or more propertiesrelate to electrical properties, magnetic properties, or a combinationthereof.

In some implementations of these embodiments, the polarization adjustingis provided via one or more Antenna Interface Standards Group(AISG)-based interfaces.

In various embodiments, an antenna system comprises a first subset ofradiating elements configured in a first manner, and a second subset ofradiating elements configured in a second manner, wherein the firstmanner is different from the second manner, resulting in polarizationadjusting that enables an impact of interference on the antenna systemto be minimized when the antenna system is operated.

In some implementations of these embodiments, the interference comprisespassive intermodulation (PIM).

In some implementations of these embodiments, the first manner isdifferent from the second manner with respect to physical shape,physical dimensions, electromagnetic properties, or any combinationthereof.

FIG. 2X depicts an illustrative embodiment of a method 280 in accordancewith various aspects described herein. In some embodiments, one or moreprocess blocks of FIG. 2X can be performed by an interference/PIMcancellation system, such as one or more of the interference/PIMcancellation systems described herein. In certain embodiments, one ormore process blocks of FIG. 2X may be performed by another device or agroup of devices separate from or including the interference/PIMcancellation system, such as a radio (e.g., an RRH), a baseband unit(BBU), an antenna or antenna system, an interference/PIM detectioncontrol device, and/or an AISG interface. In one or more embodiments,the method can include operations. For example, a device may comprise aprocessing system including a processor and associated with an antennasystem having orthogonally-polarized element pairs, and a memory thatstores executable instructions that, when executed by the processingsystem, facilitate performance of such operations.

At 282, the method can include obtaining data regarding interferencedetected in a received communication signal. For example, step 282 canbe performed in a manner similar to that described elsewhere herein.

At 284, the method can include performing polarization adjusting for oneor more orthogonally-polarized element pairs such that an impact of theinterference on an antenna system is minimized. For example, step 284can be performed in a manner similar to that described elsewhere herein.

In some implementations of these embodiments, the interferenceoriginates in a near field region of the antenna system or anintermediate field region of the antenna system that spans a portion ofthe near field region and a portion of a far field region of the antennasystem.

In some implementations of these embodiments, the performing thepolarization adjusting results in no impact to a far field region of theantenna system, as compared to a case where the polarization adjustingis not performed.

In some implementations of these embodiments, the interference comprisespassive intermodulation (PIM).

In some implementations of these embodiments, the antenna systemcomprises a multiple-input-multiple-output (MIMO) antenna.

In some implementations of these embodiments, the polarization adjustingis performed by a radio device integrated with the antenna system.

While for purposes of simplicity of explanation, the respectiveprocesses are shown and described as a series of blocks in FIG. 2X, itis to be understood and appreciated that the claimed subject matter isnot limited by the order of the blocks, as some blocks may occur indifferent orders and/or concurrently with other blocks from what isdepicted and described herein. Moreover, not all illustrated blocks maybe required to implement the methods described herein.

In various embodiments, a method comprises obtaining data regardinginterference originating from one or more interference sources, andmitigating, by an adjusting mechanism associated with an antenna systemthat comprises orthogonally-polarized element pairs, the interference byperforming polarization adjusting for the orthogonally-polarized elementpairs.

In some implementations of these embodiments, the interferenceoriginates in a near field region of the antenna system or anintermediate field region of the antenna system that spans a portion ofthe near field region and a portion of a far field region of the antennasystem.

In some implementations of these embodiments, the performing thepolarization adjusting results in no impact to a far field region of theantenna system, as compared to a case where the polarization adjustingis not performed.

In some implementations of these embodiments, the interference comprisespassive intermodulation (PIM).

In some implementations of these embodiments, the polarization adjustingis performed for both an uplink of the antenna system and a downlink ofthe antenna system.

In some implementations of these embodiments, the polarization adjustingis different for an uplink of the antenna system and a downlink of theantenna system.

In some implementations of these embodiments, the polarization adjustingis performed for an uplink of the antenna system but not a downlink ofthe antenna system.

In some implementations of these embodiments, the polarization adjustingis performed for a downlink of the antenna system but not an uplink ofthe antenna system.

In some implementations of these embodiments, the polarization adjustingcomprises mixing of signals associated with the orthogonally-polarizedelement pairs, wherein the orthogonally-polarized element pairs comprisecrossed-dipole elements.

In some implementations of these embodiments, the obtaining is performedby a processing system including a processor, wherein the adjustingmechanism is included in or comprises the processing system.

In various embodiments, a non-transitory machine-readable mediumcomprises executable instructions that, when executed by a processingsystem including a processor and associated with an antenna systemcomprising orthogonally-polarized element pairs, facilitate performanceof operations. The operations comprise receiving data regardinginterference present in a received communication signal, and performingpolarization adjusting for one or more of the orthogonally-polarizedelement pairs such that the interference is mitigated.

In some implementations of these embodiments, the interferenceoriginates in a near field region of the antenna system or anintermediate field region of the antenna system that spans a portion ofthe near field region and a portion of a far field region of the antennasystem.

In some implementations of these embodiments, the performing thepolarization adjusting results in no impact to a far field region of theantenna system, as compared to a case where the polarization adjustingis not performed.

In some implementations of these embodiments, the antenna systemcomprises a multiple-input-multiple-output (MIMO) antenna.

FIG. 3A depicts an exemplary, non-limiting embodiment of a system 300 inaccordance with various aspects described herein. In variousembodiments, the system 300 may be functioning within, or operativelyoverlaid upon, the communications network 100 of FIG. 1A and/or thecommunications system 180 of FIG. 1B. For example, portion(s) of system300 can facilitate, in whole or in part, detection of interference/PIMin a communications system and performing of action(s), such aspolarization adjusting and/or phase shifting/delaying, as describedherein, that result in mitigation/cancellation of the interference/PIM.As illustrated in FIG. 3A, a baseband processor unit (BBU) 310 comprisesa plurality of baseband processors and interfaces or connectors forconnection to a remote radio unit (RRU) 320 through a plurality of fiberoptic cables 330. BBU 310 processes downlink data signals fortransmission to mobile or stationary UEs (not illustrated) and uplinkdata signals received from mobile or stationary UEs. BBU 310 integratesmultiple lines of common public radio interface (CPRI) antenna carrierdata in full duplex at high speed over the fiber optic cables 330.

RRU 320 transmits and receives radio frequency (RF) signals from one ormore antennas 340 through RF coaxial cables 350. RRU 320 containscircuitry to convert the baseband digital signals received from BBU 310to RF signals, and vice-versa.

Optionally, inserted between BBU 310 and RRU 320 is a conditioner 360.In an embodiment, conditioner 360 can be configured to output signalsbased on a predefined protocol such as a Gigabit Ethernet output, anopen base station architecture initiative (OBSAI) protocol, or CPRIprotocol, among others. Conditioner 360 can comprise an adaptive filterconfigured to execute signal processing algorithm(s). Conditioner 360can receive digital signals, known as antenna carriers (denoted by AxC),from BBU 310 and RRU 320 via fiber optic cables 330. Each antennacarrier carries In-Phase and Quadrature (I/Q) data for one RF signal atone antenna element. In an embodiment illustrated in FIG. 3A, a 2×2 MIMOantenna 341 comprises two uplink antenna carriers on the uplink fiberand two downlink antenna carriers on the downlink fiber. I/Q datasamples are interleaved and placed in a basic frame of the antennacarrier. Samples from multiple antennas are contained in each basicframe. The uplink information can include one or more system informationblocks (SIBs) as defined by a protocol, such as, for example, an LTEprotocol. The SIBs can include a physical resource block (PRB). From aPRB, the system can obtain uplink information, which can include amongother things, an indication of how many communication devices will betransmitting wireless signals in uplink paths assigned by one or morebase stations, power level(s) that will be used by each of thecommunication devices during uplink wireless communications, theresource blocks that are assigned to each communication device, andother useful parametric information utilized by each communicationdevice when communicating via an uplink path.

In certain embodiments, the PRB can also be used by the system of thesubject disclosure to create a signal profile. The signal profile canbe, for example, an energy profile and/or a spectral profile, which canbe determined from parametric information provided in the PRB (e.g.,power level, resource blocks being used, radio access technology beingused, etc.). The signal profile can be used to determine whether thewireless signal received is a standard signal (e.g., LTE signal), and ifnot standard, whether the wireless signal received causes signalinterference. Accordingly, the signal profile can be used by the systemof the subject disclosure to perform time domain and/or frequency domainanalysis of measurements, which, in turn, can result in the detection ofsignal interferers.

The system of the subject disclosure can be adapted to perform,according to the uplink information, measurements on wireless signalstransmitted by the communication devices via the uplink paths assignedto the communication devices. The wireless signals can be received viaantennas (which, in some embodiments, may be configured as MIMOantennas). These antennas can be coupled to the system of the subjectdisclosure for performing measurements, processing and conditioning thesignals received from the antennas according to such measurements, andfor providing the conditioned signals to one or more base stationprocessors. The measurements can be based on a sampling of analogsignals supplied by an antenna receiving uplink wireless signalstransmitted by the communication devices. In other embodiments, themeasurements can be associated with measurements derived from digitalsignals supplied by one or more radio access networks (RANs) coupled toone or more corresponding antennas of a base station.

Optional conditioner 360 can provide support for 2×2 and 4×4 MIMOantenna configurations (or other MIMO configurations), diversity antennaconfigurations, and a variety of CPRI interfaces. In an embodiment,conditioner 360 supports up to 200 MHz carriers and all CPRI rates. Inan embodiment, conditioner 360 interfaces with 3 to 12 CPRI fiber pairsproviding coverage for multiple bands in, for example, a three sectorsite. Conditioner 360 can be located anywhere within fiber optic rangeof BBU 310 or RRU 320, e.g., off tower, or even off site (e.g., acentral office remote from the RRU 320).

Conditioner 360 comprises a plurality of CPRI interface cards 365. In anembodiment, each CPRI interface card 365 supports a CPRI link comprisingup to 4 antenna carriers at, for example, 5, 10, and 20 MHz bandwidths.Each CPRI link comprises either one or more frequency bands. MultipleCPRI links can comprise multiple frequency bands. Each CPRI link canfurther comprise signals associated with MIMO or diversity antennaconfigurations, and can comprise one or more sectors. For example, inone embodiment, the conditioner 360 can provide capacity for up totwelve RRUs, 48 antenna carriers, and 12 sectors. In other embodiments,the conditioner 360 can provide capacity for more or fewer RRUs, more orfewer antenna carriers, and more or fewer sectors.

Each CPRI interface card 365 can examine SIBs obtained from one or moredownlink fibers to determine parameters of the uplink path signalsreceived over the uplink fiber. In an embodiment, the CPRI interfacecard 365 can take SINR measurements of each uplink path according toinformation in the SIBs obtained from the one or more downlink fibers,and determine whether one or more SINR measurements fall below athreshold. In some embodiments, the CPRI interface card 365 can takecorrective action to improve one or more SINR measurements falling belowthe threshold, such as moving an uplink path affected by interference toan available uplink path in the same sector, or in different sectors, asset forth in more detail below. In an embodiment, the CPRI interfacecard 365 can compare signals from different sectors to determine anapproach for taking corrective action.

It will be appreciated that the threshold noted above can represent aminimally expected SINR measurement. It will be appreciated that thethreshold compared against one or more SINR measurements can be apredetermined threshold. In other embodiments, the threshold can bedetermined empirically from measurements taken in a controlled settingto identify a desirable SINR measurement. In yet other embodiments, thethreshold can be determined according to a running average of powerlevels within a resource block or among groupings of resource blocks.Other techniques for determining a threshold that is compared to a SINRmeasurement can be used. Similarly, correlation techniques can be usedto identify circumstances that warrant corrective action of certain SINRmeasurements.

It is to be appreciated and understood that some or all of the aspectsof detection of interference/PIM and/or polarization adjusting and/orphase shifting/delaying, described herein, can be performed in, or by,one or more of the antennas 340, one or more of the RRUs 320, one ormore of the BBUs 310, and/or the optional conditioner 360.

FIG. 3B depicts an exemplary, non-limiting embodiment of a system fordetecting passive intermodulation (PIM) interferences in uplink signalsof a base station in accordance with various aspects described herein.In various embodiments, this system may be functioning within, oroperatively overlaid upon, the communications network 100 of FIG. 1Aand/or the communications system 180 of FIG. 1B. For example, portion(s)of this system can facilitate, in whole or in part, detection ofinterference/PIM in a communications system and performing of action(s),such as polarization adjusting and/or phase shifting/delaying, asdescribed herein, that result in mitigation/cancellation of theinterference/PIM.

As illustrated in FIG. 3B, inserted between BBUs (not illustrated) andRRUs 370A is a PIM detector 370, which non-intrusively receives andsupplies signals through a plurality of fiber optic cables 370B, whichcomprise multiple lines of CPRI antenna carrier data in full duplex athigh speed over the fiber optic cables 370B. The PIM detector 370 can beinstalled remotely from the base station. RRUs 370A transmit and receiveradio frequency (RF) signals from one or more antennas 370C through RFcoaxial cables 370D, denoted as “paths.”

PIM detector 370 illustrated in FIG. 3B measures the presence of PIM inone band and in one or multiple paths of an uplink based on detectionalgorithms applied to the measured signals. PIM detector 370 can rankthe source of PIM due to a junction, cables or components, or anantenna. PIM detector 370 can quantify the PIM interference level, fromlow, moderate, to severe.

Knowing that a transmission signal on the same line is strong, if theline is duplexed, can indicate a PIM issue, and generally is an internalproblem to the base station. Based on the level of PIM measured andcorrelation to received signal strength indicator (RSSI), adetermination of the magnitude of the problem will be evaluated. Forexample, if the level of PIM on Path 1 and on Path 2 are correlated,then it is more likely an external PIM is present. If there is nocorrelation, it is likely an internal PIM is present due to a particularcomponent of the base station. By assessing a signature of the PIM, PIMdetector 370 can detect whether the source of interference is due to anLTE band signal, or due to other cellular technologies, or evennon-cellular sources. As shown in FIG. 3B, if PIM is measured and isavailable on multiple bands that share the same cables and antenna, itis likely that a particular component or cable of a base station is thesource of PIM.

Correlation with time can also be detected if PIM interference happensduring a particular time when the system is heavily used and the PIMlevel can be correlated to another transmitter.

In an embodiment, a sequence of steps in a method are performed in whichtransmitters are turned on at different high power levels during amaintenance window and in certain combination(s) so that the PIMdetector can determine if the PIM happens at certain target bands andunder certain conditions. As illustrated in FIG. 3B, a cellular networkcarrier supplies 8 RF bands or services to a base station comprisingfour antennas 370C in the mobile network. Each band/service may comprise2 paths, or possibly 4 paths. As illustrated in FIG. 3B, four antennas370C comprise the 8 bands/services supplied by the carrier, over a totalof 24 paths, two paths for the low frequency band, and four paths forthe high frequency band on each antenna.

In the method, PIM detector 370 builds an array of 24 RSSI measurements,one RSSI measurement for each path, while transmission occurs on onepath, preferably under a simulated high traffic condition. Such hightraffic condition can be simulated with the help of an Air interfaceload generator (AILG) or an Orthogonal channel noise simulator (OCNS)that creates signals at different frequencies, so that the level of PIMcan be detected and determined. Another array of 24 RSSI measurements isbuilt by PIM detector 370 while transmission occurs only on the secondpath, and so forth. Each transmission path is used to create a row in a24×24 matrix M of RSSI measurements formed by the various transmissions:

24[²⁴]=Mi, where i denotes the power level.

Next, PIM detector 370 changes the power level of the transmissions,thereby forming a series of matrices. By comparing the RSSI in eachmatrix to the next one, PIM detector 370 can determine whether thetransmissions are creating leakage, or possibly internal PIM from aparticular transmission path. If increasing power with Mi has an impacton the RSSI reading, then the interference is PIM, and internal PIM inparticular. If the change in RSSI when power is doubled is 2 dBc, thenthe interference can be characterized as a 3rd order PIM. If theincrease is ≈3-8 dBc, then the interference can be characterized as 5thorder PIM. If increasing power with Mi does not have an impact on theRSSI reading, then the interference is external.

In an embodiment, different combinations of bands and/or paths that canbe impacted by PIM arise from multiple transmissions. From suchcombinations of bands and/or paths, PIM detector 370 can be configuredto determine if the PIM is caused by an internal component of a basestation or an external component that is not part of the base station(e.g., an external metallic object that reflects a signal transmissionfrom the base station). PIM detector 370 can measure interference basedon the detection algorithms in multiple bands and/or multiple pathsbased on the multiple transmissions. For example, consider that, if onlytwo transmitters are transmitting in two bands out of the eight bands,there would be (8!/6!/2!) combinations, or 28 possible dual bandtransmission cases for the base station illustrated in FIG. 3B. If threetransmitters out of the eight bands were transmitting at the same timeto cause the PIM, there would be (8!/5!/3!) combinations, or 56 possibletri-band transmission cases for the base station of FIG. 3B. If fourtransmitters out of the eight bands were transmitting at the same timeto cause the PIM, there would be (8!/4!/4!) combinations, or 70 possiblequad-band transmission cases for the base station of FIG. 3B. If all 154possible transmission combinations (28+56+70) are considered, then amatrix MCi can be formed by measuring the RSSI in each of the 24 paths:

154[²⁴]=M C i, where i denotes the power level.

By comparing the RSSI levels under different power levels andconditions, PIM detector 370 can determine whether there is a certaincombination that creates PIM interference, whether the interference is afunction of certain frequency bands, or whether the interference is afunction of certain antenna proximity issues. By repeating the testtransmissions at other sectors, further diagnosis can be performed.

Once PIM interference has been detected, corrective actions may include,for example, applying one or more polarization adjusting and/or phaseshifting/delaying techniques described herein; resolving issues relatedto variability among sectors; or looking at MCi and evaluating theincrease in RSSI at different levels to determine what order level PIM(3rd, 5th, etc.) is causing the interference. Additionally, the impacton performance under different loading conditions can be considered. Forexample, the delta increase in RSSI can be correlated to a certain powerlevel, and as a result, the offending transmission should be reduced.Another case is when the optimum level of transmission is determined fora particular traffic condition on one of the 8 transmitters. Thisprocess may be repeated for each band.

In an embodiment, interference detection may be extended in severalways: the matrices of a particular sector may be correlated with that ofanother sector in the same site, and as a result, determine if there areissues in particular with antenna isolation, or more of a systemicissue; the matrix element of a particular sector can be correlated todetermine the integrity of the RF environment and the quality of RFsignals; or detection algorithms can determine the LTE quality. In anembodiment, the matrices of a particular site can be correlated withthose of a neighboring site (taking into consideration that the othersite may have a different antenna configuration or isolation but thesame frequency bands). In this case, the information can help increasethe confidence level in determining if the PIM is internal or external,and if it's external, what bands are targeted. The information can helpdetect if the PIM or interference is coming from another competitivecarrier or is self-inflicted due to the multiple bands in operation.(For example, peak and quiet time tends to be the same for all carriersand therefore maintenance window testing can rule out or confirm thesource.)

In another embodiment, RSSI elements in the matrices could be replacedwith spectral pictures in which the information can be segmented furtherinto an array of frequencies. This will give further insight and provideinformation on the mixing combinations and determine if there areleakages instead of PIM. Also, any correlation with power levels can beused to determine the order of the PIM. In an embodiment, the system canbe automated to perform carrier testing at maintenance window, whichwill provide a wealth of information on the quality of the network.

FIG. 3C illustrates a block diagram depicting an example, non-limitingembodiment of a communication system 385 including a virtualizedinterference mitigation network in accordance with various aspectsdescribed herein. In various embodiments, the communications system 385may be functioning within, or operatively overlaid upon, thecommunications network 100 of FIG. 1A and/or the communications system180 of FIG. 1B.

As depicted in FIG. 3C, a virtualized interference mitigation network ispresented that can be used to implement some or all of the methods forinterference mitigation described herein. For example, portion(s) ofthis network can facilitate, in whole or in part, detection ofinterference/PIM in a communications system and performing of action(s),such as polarization adjusting and/or phase shifting/delaying, asdescribed herein, that result in mitigation/cancellation of theinterference/PIM. In one or more embodiments, communication system 385may be configured to provide conditioning of uplink signals.Communication system 385 can include remote radio units (RRU) 320 andone or more antennas 340. The RRUs 320 can transmit and receive radiofrequency (RF) signals to and from the one or more antennas 340 throughRF coaxial cables 350. The RRUs 320 can include circuitry to convert thebaseband digital signals to RF signals, and vice-versa. In oneembodiment, the RRUs 320 can be coupled to fiber optic cables 330. Inone embodiment, the fiber optic cables 330 can carry digital data to andfrom the RRUs. In one embodiment, a common public radio interface (CPRI)protocol can be used to carry digital data to and from the RRUs 320 viafull duplex at high speed over the fiber optic cables 330.

The digital data, also known as antenna carriers (denoted by AxC), canoriginate from the RRUs 320 or from virtual BBUs 385A. In oneembodiment, each antenna carrier can include I/Q data for an RF signalassociated with an antenna element. I/Q data can describe aninstantaneous state of an RF signal by providing magnitude and phaseangle information based on sinusoidal modeling of the RF signal. If anRF signal is used for modulating a voice/data signal on a carrier wave,then I/Q data can effectively convey information about the data beingcarried. In addition, I/Q data can be provided in a Cartesian coordinatesystem (X, Y), where X=amplitude and Y=phase angle. In an embodimentillustrated in FIG. 3C, a 2×2 MIMO antenna 341 can include two uplinkantenna carriers on the uplink fiber and two downlink antenna carrierson the downlink fiber. I/Q data samples can be interleaved and placed ina basic frame of the antenna carrier. Samples from multiple antennas arecontained in each basic frame.

In one or more embodiments, the communication system 385 can includevirtualized interference mitigation, where functions for interferencedetection, mitigation (e.g., via polarization adjusting and/or phaseshifting/delaying as described herein), and baseband communicationsserving uplink and downlink paths can be implemented via a cloudnetworking architecture 386. In particular, a cloud networkingarchitecture 386 is shown that can leverage cloud technologies andsupports innovation and scalability. The cloud networking architecture386 for virtualized interference mitigation can include a transportlayer 387 and/or one or more virtualized network function clouds 385D.The cloud networking architecture 386 can also include one or more cloudcomputing environments 385E. In various embodiments, this cloudnetworking architecture 386 can be implemented via an open architecturethat leverages application programming interfaces (APIs), which canseamlessly scale to meet evolving customer requirements includingtraffic growth, diversity of traffic types, and diversity of performanceand reliability expectations.

In one or more embodiments, the cloud networking architecture 386 canemploy virtualized network function clouds 385D to perform some or allof the functions of interference detection and mitigation (e.g., viapolarization adjusting and/or phase shifting/delaying) described herein.The virtualized network function clouds 385D can include virtual networkfunctions (VFN) or virtual network elements (VFE) to perform some or allof the functions for interference detection and mitigation (e.g., viapolarization adjusting and/or phase shifting/delaying) as describedherein. For example, the virtualized network function clouds 385D canprovide a substrate of networking capability, often called NetworkFunction Virtualization Infrastructure (NFVI) or simply infrastructurethat is capable of being directed with software and Software DefinedNetworking (SDN) protocols. In one embodiment, the virtualized networkfunction clouds 385D can include one or more a SDN Controllers 385C thatcan direct, control, and/or modify the operation of the virtualizednetwork function clouds 385D and of the VFE and/or VFE that areinstantiated in the virtualized network function clouds 385D. Thevirtualized network function clouds 385D can support Network FunctionVirtualization (NFV).

As an example, an interference mitigation function, such as aninterference/PIM cancellation block (e.g., the interference/PIMcancellation block 203 c of FIG. 2C or the like), an interference/PIMdetection control device (e.g., interference/PIM detection controldevice 203 d of FIG. 2C or the like), an adaptive front-end module,and/or the like can be implemented via a VNE composed of NFV softwaremodules, merchant silicon, and/or associated controllers. Theinterference mitigation function can be in the form of a VirtualInterference Mitigation Service that is instantiated into thevirtualized network function cloud 385D by the SDN Controller 385C.Various interference mitigation functions can be instantiated in thevirtualized network function clouds 385D, such as, but not limited to,systems and/or methods for signal processing, interference detection,adaptive threshold determination, interference/PIM mitigation (e.g., viapolarization adjusting and/or phase shifting/delaying, as describedherein), network adaptation and optimization, and/or link analysis,optimization, and/or management. Other interference mitigation functionscan be instantiated in the virtualized network function clouds 385D,such as, but not limited to, systems and/or methods for adaptinginter-cell interference thresholds based on thermal noise, conditioninguplink signals, and general interference diagnosis and testing.

In one or more embodiments, software can be written so that increasingworkload on the virtualized network function clouds 385D consumesincremental resources from a common resource pool, and moreover so thatit's elastic: so the resources are only consumed when needed. In asimilar fashion, virtual interference mitigation servers 385B, virtualBBUs 385A, and other network elements, such as other routers, switches,edge caches, and middle-boxes, can be instantiated from a commonresource pool as directed by a SDN Controller 385C. Such sharing ofinfrastructure across a broad set of uses makes planning and growinginfrastructure easier to manage.

In an embodiment, the cloud networking architecture 386 can include atransport layer 387. The transport layer 387 can include fiber, cable,wired and/or wireless transport elements, network elements andinterfaces to transmit digital signals to and from the RRUs 320 to thevirtualized network function clouds 385D. In one example, fiber opticcable 330 can transmit digital signals between the RRUs 320 and thevirtualized network function cloud 385D, and the transport layer 387simply be a continuation of the fiber optic cable and/or includerepeating and/or buffering functions. In one example, the transportlayer 387 can translate the digital signals between the fiber opticcable 330 and other transport media, such as wired or wirelessconnections. In one embodiment, a network element, such as a virtual BBU385A, may need to be positioned at a specific location. For example, abank of virtual BBUs 385A may be physically co-located to take advantageof common infrastructure. To optimally link digital signals between aclient RRU 320 and a virtual BBU 385A that is in a remote location, thetransport layer 387 may convert between a communication media, such as afiber optic link to the RRU 320, and a long-haul media, such as theInternet or a cellular system. In one embodiment, a network element,such as a BBU, may include physical layer adapters that cannot beabstracted or virtualized, or that might require special DSP code andanalog front-ends (AFEs), such that the network element cannot becompletely virtualized. In this case, all or part of the network elementmay be included in the transport layer 387.

The virtualized network function clouds 385D can interface with thetransport layer 387 to provide virtual network elements, such as virtualinterference mitigation servers 385B and virtual BBUs 385A, that providespecific NFVs. In particular, the virtualized network function cloud385D can leverage cloud operations, applications, and architectures tosupport communication loading and required interference mitigation. Forexample, virtual interference mitigation servers 385B and virtual BBUs385A can employ network function software that provides either aone-for-one mapping of non-networked versions of these functions or,alternately, combines versions of these functions that are designedand/or optimized for cloud computing. For example, virtual interferencemitigation servers 385B and virtual BBUs 385A, or other ancillarynetwork devices, may be able to process digital data signals withoutgenerating large amounts of network traffic. As such, their workload canbe distributed across a number of servers within and/or between eachvirtualized network function cloud 385D. Each of the virtualinterference mitigation servers 385B and virtual BBUs 385A can add itsportion of capability to the whole, so that the cloud networkingarchitecture 386 exhibits an overall elastic function with higheravailability than a strictly monolithic version. These virtualinterference mitigation servers 385B and virtual BBUs 385A can beinstantiated and managed by a SDN Controller 385C using an orchestrationapproach similar to those used in cloud compute services.

In one or more embodiments, the virtualized network function clouds 385Dcan further interface with other cloud computing environments 385E viaapplication programming interfaces (API) that can expose functionalcapabilities of the virtual interference mitigation servers 385B andvirtual BBUs 385A to provide flexible and expanded capabilities to thevirtualized network function cloud 385D. In particular, interferencemitigation workloads may have applications distributed across thevirtualized network function clouds 385D and the cloud computingenvironment 385E (at third-party vendors). The SDN Controller 385C mayorchestrate workloads supported entirely in NFV infrastructure fromthese third-party locations.

In one or more embodiments, a virtual interference mitigation server385B at a virtualized network function cloud 385D can be configured toreceive digital signals from RRUs 320 operating at a communicationssite, such as at a cellular tower. The virtual interference mitigationserver 385B can rely on the digital nature of the digital signals(converted from the RF domain prior to transmission on the fiber opticcables 330), the transport layer 387, and the virtualized networkfunction cloud 385D to facilitate remote processing of digital signalsrepresenting RF signals received at the RRUs 320. In one embodiment, thevirtual interference mitigation server 385B can perform measurements onthese digital signals for detecting interference on RF signals, and caninitiate mitigation for detected interference.

In one or more embodiments, the virtual interference mitigation server385B can perform measurements on digital data that it receives via thetransport layer 387. The virtual interference mitigation server 385B caninclude interfaces capable of interfacing with the digital signals in aprotocol, such as the common public radio interface (CPRI) protocol. Inone embodiment, the virtual interference mitigation server 385B caninclude one or more protocol-capable interface cards. In one embodiment,the virtual interference mitigation server 385B can implement protocolcompatibility via hardware, software, or a combination of hardware andsoftware. In one embodiment, each virtual interference mitigation server385B can support one or more data links (CPRI-capable links). Each datalink can include one or more frequency bands. Multiple data links caninclude multiple frequency bands. Each data link can further includesignals associated with multiple-input and multiple-output (MIMO)antennas 341 or diversity antenna configurations. Each data link cansupport one or more sectors. For example, a virtual interferencemitigation server 385B can provide capacity for banks of RRUs 320,antenna carriers, and sectors at multiple cell locations.

In one or more embodiments, the virtual interference mitigation server385B can examine system information blocks (SIB s) to determineparameters of the uplink path signals received over the transport layer387. In an embodiment, the virtual interference mitigation server 385Bcan obtain SINR measurements of uplink paths according to digital signalinformation from SIBs. The virtual interference mitigation server 385Bcan determine whether one or more SINR measurements fall below athreshold and, in turn, can take corrective action to improve one ormore SINR measurements that fall below the threshold. For example, thevirtual interference mitigation server 385B can determine a correctiveaction, whereby an uplink path that is affected by interference is movedto an available uplink path in the same sector, or in different sectors.In an embodiment, the virtual interference mitigation server 385B cancompare signals from different sectors to determine an approach fortaking corrective action.

In one or more embodiments, the virtual interference mitigation server385B can (e.g., optionally) include a conditioner function. Thecondition function can include an adaptive filter, and/or can executesignal processing algorithm(s). The conditioner of the virtualinterference mitigation server 385B can receive digital signals from thetransport layer 387, where these digital signals represent RF signalsthat are received at the RRU 320. The conditioner of the virtualinterference mitigation server 385B can provide support for 2×2 and 4×4MIMO antenna configurations (or other MIMO configurations), diversityantenna configurations, and a variety of CPRI interfaces. In oneembodiment, the conditioner can be co-located at the virtualinterference mitigation server 385B. In other embodiments, theconditioner can be located anywhere, including at the virtual BBU 385A,the RRU 320, the transport layer 387, and/or at a second virtualizednetwork function cloud 385D or a cloud computing environment 385E.

In one or more embodiments, the virtual BBU 385A provides digitalcommunications to the RRU 320. In one embodiment, a virtual BBU 385Athat is directing a RRU 320 can be located in the same virtualizednetwork function cloud 385D as a virtual interference mitigation server385B that is performing interference measurements on digital signalsfrom this same RRU 320. In this way, a SDN Controller 385C at thevirtualized network function cloud 385D can coordinate instantiation,configuration, and, if needed, decommissioning of the virtual BBU 385Aand the virtual interference mitigation server 385B. In one embodiment,the virtual BBU 385A and the virtual interference mitigation server 385Bcan be instantiated into different virtualized network function clouds385D. In this situation, multiple SDN Controllers 385C and virtualizednetwork function clouds 385D may be involved in managing these VNE.

FIG. 3D depicts an illustrative non-limiting embodiment of a method 388for performing virtual interference mitigation. Method 388 can becombined or adapted in whole or in part with other embodiments of thesubject disclosure including other methods described herein. Beginningwith step 388A, a virtual interference mitigation server 385B of thesubject disclosure can be adapted to obtain digital data representing RFsignals of uplink paths associated with RRUs 320 in communication withcommunication devices (e.g., mobile phones, tablets, stationarycommunication devices, etc.) that transmit wireless signals on theuplink paths. Uplink instructions are generally sent to communicationdevices via downlink wireless signals to enable the communicationdevices to engage in uplink wireless communications. In otherembodiments, the virtual interference mitigation server 385B can obtainuplink information based on information provided by a transport layer387. The uplink instructions can include SIBs from which the systemperforming method 388 can obtain uplink information, including anindication of how many communication devices will be transmittingwireless signals in uplink paths assigned by one or more base stations,power level(s) that will be used by each of the communication devicesduring uplink wireless communications, the resource blocks that areassigned to each communication device, and other useful parametricinformation utilized by each communication device when communicating viaan uplink path.

In one or more embodiments, at step 388B, the virtual interferencemitigation server 385B of the subject disclosure can be adapted toperform measurements of the digital signals of the uplink paths assignedto the communication devices. Wireless signals from the communicationdevices can be received via antennas 340. These antennas 340 can becoupled to RRUs 320, which can generate the digital signals representingthe RF signals that have been received. In one or more embodiments, thevirtual interference mitigation server 385B can perform measurements,processing, and/or conditioning of the digital signals received from thetransport layer 387.

At step 388C, the virtual interference mitigation server 385B can beadapted to detect signal interference in one or more of the measurementsperformed at step 388B based on such measurements that compareunfavorably to one or more thresholds. As noted earlier, the uplinkinformation can include, but is not limited to, the number ofcommunication devices that will be transmitting in uplink paths, thepower level(s) used by each communication devices while transmittingduring one or more assigned resource blocks, the resource blocks thathave been assigned to each communication device, and other usefulparametric information utilized by each communication device whencommunicating via an uplink path.

The number of communication devices transmitting wireless signals onuplink paths can be used to determine a density of spectral energyexpected in certain resource blocks and at certain time slots. Withprior knowledge of the transmission characteristics used by eachcommunication device, the system can be adapted to determine a thresholdper resource block based on an expected power level for eachcorresponding resource block, an overall threshold based on an expectedaverage power level across groups of resource blocks, a timing of theuse of the resource blocks by the communication devices, or combinationsthereof. A threshold can be determined statically, or dynamically as arunning average of power levels. In an embodiment, the measurementsperformed at step 388B can be based on SINR (or other) measurements. Atstep 388C, the system of the subject disclosure can be further adaptedto identify one or more affected uplink paths based on one or moremeasurements that compare unfavorably to the one or more thresholds ofstep 388B.

Responsive to identifying the affected paths and thereby detectingsignal interference in such paths based on the threshold(s), the virtualinterference mitigation server 385B of the subject disclosure can beadapted to take corrective actions in step 388D to improve themeasurements of the affected paths. The affected uplink path can beaffected by interference signals as described in the subject disclosure.The corrective action can include without limitation, singly or incombination, locating unused uplink paths that are not affected by theinterference, suppressing one or more interference signals on theaffected uplink paths, adjusting the number of communication deviceallowed to transmit wireless signals on the affected uplink paths,and/or by performing other mitigation techniques (e.g., polarizationadjusting and/or phase shifting/delaying techniques) described in thesubject disclosure.

At step 388E, the virtual interference mitigation server 385B can beadapted to provide updated digital data to one or more virtual BBU 385Ato implement a corrective action. The virtual interference mitigationserver 385B of the subject disclosure can instruct one or more virtualBBUs 385A to effect one or more polarization adjusting and/or phaseshifting/delaying techniques described herein. Additionally, oralternatively, the virtual interference mitigation server 385B caninstruct one or more virtual BBUs 385A to move transmissions to one ormore uplink paths different from the one or more affected uplink paths,instruct one or more of the plurality of communication devices to moveto one or more uplink paths to uplink paths located in differentsectors, or to move affected uplink paths to different uplink paths of adifferent base station, or any combinations thereof. The differentuplink paths moved to can be unused, and thus, available uplink paths.In an embodiment, the virtual interference mitigation server 385B of thesubject disclosure can check the noise and/or interference level of theavailable uplink paths to ensure that better communications can beprovided as a result of moving from the affected uplink paths.

The foregoing embodiments can be adapted for other applications as well.For example, the uplink information can be used by the system of thesubject disclosure to determine PRB utilization, which can be reportedto a base station processor. Based on interference detection andmitigation across one or more resource blocks, the system of the subjectdisclosure can be further adapted to provide recommendations and/ordirect a base station processor to modify SIBs to improve PRButilization in one or more uplink paths.

While for purposes of simplicity of explanation, the respectiveprocesses are shown and described as a series of blocks in FIG. 3D,respectively, it is to be understood and appreciated that the claimedsubject matter is not limited by the order of the blocks, as some blockscan occur in different orders and/or concurrently with other blocks fromwhat is depicted and described herein. Moreover, not all illustratedblocks may be required to implement the methods described herein.

Turning now to FIG. 4, there is illustrated a block diagram of acomputing environment in accordance with various aspects describedherein. In order to provide additional context for various embodimentsof the embodiments described herein, FIG. 4 and the following discussionare intended to provide a brief, general description of a suitablecomputing environment 400 in which the various embodiments of thesubject disclosure can be implemented. In particular, computingenvironment 400 can be used in the implementation of network elements150, 152, 154, 156, access terminal 112, base station or access point122, switching device 132, media terminal 142, and/or one or moredevices/components/systems of FIGS. 3A-3C, etc. Each of these devicescan be implemented via computer-executable instructions that can run onone or more computers, and/or in combination with other program modulesand/or as a combination of hardware and software. For example, computingenvironment 400 can facilitate, in whole or in part, detection ofinterference/PIM in a communications system and performing of action(s),such as polarization adjusting and/or phase shifting/delaying, asdescribed herein, that result in mitigation/cancellation of theinterference/PIM.

Generally, program modules comprise routines, programs, components, datastructures, etc., that perform particular tasks or implement particularabstract data types. Moreover, those skilled in the art will appreciatethat the methods can be practiced with other computer systemconfigurations, comprising single-processor or multiprocessor computersystems, minicomputers, mainframe computers, as well as personalcomputers, hand-held computing devices, microprocessor-based orprogrammable consumer electronics, and the like, each of which can beoperatively coupled to one or more associated devices.

As used herein, a processing circuit includes one or more processors aswell as other application specific circuits such as an applicationspecific integrated circuit, digital logic circuit, state machine,programmable gate array or other circuit that processes input signals ordata and that produces output signals or data in response thereto. Itshould be noted that while any functions and features described hereinin association with the operation of a processor could likewise beperformed by a processing circuit.

The illustrated embodiments of the embodiments herein can be alsopracticed in distributed computing environments where certain tasks areperformed by remote processing devices that are linked through acommunications network. In a distributed computing environment, programmodules can be located in both local and remote memory storage devices.

Computing devices typically comprise a variety of media, which cancomprise computer-readable storage media and/or communications media,which two terms are used herein differently from one another as follows.Computer-readable storage media can be any available storage media thatcan be accessed by the computer and comprises both volatile andnonvolatile media, removable and non-removable media. By way of example,and not limitation, computer-readable storage media can be implementedin connection with any method or technology for storage of informationsuch as computer-readable instructions, program modules, structured dataor unstructured data.

Computer-readable storage media can comprise, but are not limited to,random access memory (RAM), read only memory (ROM), electricallyerasable programmable read only memory (EEPROM), flash memory or othermemory technology, compact disk read only memory (CD-ROM), digitalversatile disk (DVD) or other optical disk storage, magnetic cassettes,magnetic tape, magnetic disk storage or other magnetic storage devicesor other tangible and/or non-transitory media which can be used to storedesired information. In this regard, the terms “tangible” or“non-transitory” herein as applied to storage, memory orcomputer-readable media, are to be understood to exclude onlypropagating transitory signals per se as modifiers and do not relinquishrights to all standard storage, memory or computer-readable media thatare not only propagating transitory signals per se.

Computer-readable storage media can be accessed by one or more local orremote computing devices, e.g., via access requests, queries or otherdata retrieval protocols, for a variety of operations with respect tothe information stored by the medium.

Communications media typically embody computer-readable instructions,data structures, program modules or other structured or unstructureddata in a data signal such as a modulated data signal, e.g., a carrierwave or other transport mechanism, and comprises any informationdelivery or transport media. The term “modulated data signal” or signalsrefers to a signal that has one or more of its characteristics set orchanged in such a manner as to encode information in one or moresignals. By way of example, and not limitation, communication mediacomprise wired media, such as a wired network or direct-wiredconnection, and wireless media such as acoustic, RF, infrared and otherwireless media.

With reference again to FIG. 4, the example environment can comprise acomputer 402, the computer 402 comprising a processing unit 404, asystem memory 406 and a system bus 408. The system bus 408 couplessystem components including, but not limited to, the system memory 406to the processing unit 404. The processing unit 404 can be any ofvarious commercially available processors. Dual microprocessors andother multiprocessor architectures can also be employed as theprocessing unit 404.

The system bus 408 can be any of several types of bus structure that canfurther interconnect to a memory bus (with or without a memorycontroller), a peripheral bus, and a local bus using any of a variety ofcommercially available bus architectures. The system memory 406comprises ROM 410 and RAM 412. A basic input/output system (BIOS) can bestored in a non-volatile memory such as ROM, erasable programmable readonly memory (EPROM), EEPROM, which BIOS contains the basic routines thathelp to transfer information between elements within the computer 402,such as during startup. The RAM 412 can also comprise a high-speed RAMsuch as static RAM for caching data.

The computer 402 further comprises an internal hard disk drive (HDD) 414(e.g., EIDE, SATA), which internal HDD 414 can also be configured forexternal use in a suitable chassis (not shown), a magnetic floppy diskdrive (FDD) 416, (e.g., to read from or write to a removable diskette418) and an optical disk drive 420, (e.g., reading a CD-ROM disk 422 or,to read from or write to other high capacity optical media such as theDVD). The HDD 414, magnetic FDD 416 and optical disk drive 420 can beconnected to the system bus 408 by a hard disk drive interface 424, amagnetic disk drive interface 426 and an optical drive interface 428,respectively. The hard disk drive interface 424 for external driveimplementations comprises at least one or both of Universal Serial Bus(USB) and Institute of Electrical and Electronics Engineers (IEEE) 1394interface technologies. Other external drive connection technologies arewithin contemplation of the embodiments described herein.

The drives and their associated computer-readable storage media providenonvolatile storage of data, data structures, computer-executableinstructions, and so forth. For the computer 402, the drives and storagemedia accommodate the storage of any data in a suitable digital format.Although the description of computer-readable storage media above refersto a hard disk drive (HDD), a removable magnetic diskette, and aremovable optical media such as a CD or DVD, it should be appreciated bythose skilled in the art that other types of storage media which arereadable by a computer, such as zip drives, magnetic cassettes, flashmemory cards, cartridges, and the like, can also be used in the exampleoperating environment, and further, that any such storage media cancontain computer-executable instructions for performing the methodsdescribed herein.

A number of program modules can be stored in the drives and RAM 412,comprising an operating system 430, one or more application programs432, other program modules 434 and program data 436. All or portions ofthe operating system, applications, modules, and/or data can also becached in the RAM 412. The systems and methods described herein can beimplemented utilizing various commercially available operating systemsor combinations of operating systems.

A user can enter commands and information into the computer 402 throughone or more wired/wireless input devices, e.g., a keyboard 438 and apointing device, such as a mouse 440. Other input devices (not shown)can comprise a microphone, an infrared (IR) remote control, a joystick,a game pad, a stylus pen, touch screen or the like. These and otherinput devices are often connected to the processing unit 404 through aninput device interface 442 that can be coupled to the system bus 408,but can be connected by other interfaces, such as a parallel port, anIEEE 1394 serial port, a game port, a universal serial bus (USB) port,an IR interface, etc.

A monitor 444 or other type of display device can be also connected tothe system bus 408 via an interface, such as a video adapter 446. Itwill also be appreciated that in alternative embodiments, a monitor 444can also be any display device (e.g., another computer having a display,a smart phone, a tablet computer, etc.) for receiving displayinformation associated with computer 402 via any communication means,including via the Internet and cloud-based networks. In addition to themonitor 444, a computer typically comprises other peripheral outputdevices (not shown), such as speakers, printers, etc.

The computer 402 can operate in a networked environment using logicalconnections via wired and/or wireless communications to one or moreremote computers, such as a remote computer(s) 448. The remotecomputer(s) 448 can be a workstation, a server computer, a router, apersonal computer, portable computer, microprocessor-based entertainmentappliance, a peer device or other common network node, and typicallycomprises many or all of the elements described relative to the computer402, although, for purposes of brevity, only a remote memory/storagedevice 450 is illustrated. The logical connections depicted comprisewired/wireless connectivity to a local area network (LAN) 452 and/orlarger networks, e.g., a wide area network (WAN) 454. Such LAN and WANnetworking environments are commonplace in offices and companies, andfacilitate enterprise-wide computer networks, such as intranets, all ofwhich can connect to a global communications network, e.g., theInternet.

When used in a LAN networking environment, the computer 402 can beconnected to the LAN 452 through a wired and/or wireless communicationsnetwork interface or adapter 456. The adapter 456 can facilitate wiredor wireless communication to the LAN 452, which can also comprise awireless AP disposed thereon for communicating with the adapter 456.

When used in a WAN networking environment, the computer 402 can comprisea modem 458 or can be connected to a communications server on the WAN454 or has other means for establishing communications over the WAN 454,such as by way of the Internet. The modem 458, which can be internal orexternal and a wired or wireless device, can be connected to the systembus 408 via the input device interface 442. In a networked environment,program modules depicted relative to the computer 402 or portionsthereof, can be stored in the remote memory/storage device 450. It willbe appreciated that the network connections shown are example and othermeans of establishing a communications link between the computers can beused.

The computer 402 can be operable to communicate with any wirelessdevices or entities operatively disposed in wireless communication,e.g., a printer, scanner, desktop and/or portable computer, portabledata assistant, communications satellite, any piece of equipment orlocation associated with a wirelessly detectable tag (e.g., a kiosk,news stand, restroom), and telephone. This can comprise WirelessFidelity (Wi-Fi) and BLUETOOTH® wireless technologies. Thus, thecommunication can be a predefined structure as with a conventionalnetwork or simply an ad hoc communication between at least two devices.

Wi-Fi can allow connection to the Internet from a couch at home, a bedin a hotel room or a conference room at work, without wires. Wi-Fi is awireless technology similar to that used in a cell phone that enablessuch devices, e.g., computers, to send and receive data indoors and out;anywhere within the range of a base station. Wi-Fi networks use radiotechnologies called IEEE 802.11 (a, b, g, n, ac, ag, etc.) to providesecure, reliable, fast wireless connectivity. A Wi-Fi network can beused to connect computers to each other, to the Internet, and to wirednetworks (which can use IEEE 802.3 or Ethernet). Wi-Fi networks operatein the unlicensed 2.4 and 5 GHz radio bands for example or with productsthat contain both bands (dual band), so the networks can providereal-world performance similar to the basic 10BaseT wired Ethernetnetworks used in many offices.

Turning now to FIG. 5, an embodiment 500 of a mobile network platform510 is shown that is an example of network elements 150, 152, 154, 156,and/or one or more devices/components/systems of FIGS. 3A-3C, etc. Forexample, platform 510 can facilitate, in whole or in part, detection ofinterference/PIM in a communications system and performing of action(s),such as polarization adjusting and/or phase shifting/delaying, asdescribed herein, that result in mitigation/cancellation of theinterference/PIM. In one or more embodiments, the mobile networkplatform 510 can generate and receive signals transmitted and receivedby base stations or access points such as base station or access point122. Generally, mobile network platform 510 can comprise components,e.g., nodes, gateways, interfaces, servers, or disparate platforms, thatfacilitate both packet-switched (PS) (e.g., internet protocol (IP),frame relay, asynchronous transfer mode (ATM)) and circuit-switched (CS)traffic (e.g., voice and data), as well as control generation fornetworked wireless telecommunication. As a non-limiting example, mobilenetwork platform 510 can be included in telecommunications carriernetworks, and can be considered carrier-side components as discussedelsewhere herein. Mobile network platform 510 comprises CS gatewaynode(s) 512 which can interface CS traffic received from legacy networkslike telephony network(s) 540 (e.g., public switched telephone network(PSTN), or public land mobile network (PLMN)) or a signaling system #7(SS7) network 560. CS gateway node(s) 512 can authorize and authenticatetraffic (e.g., voice) arising from such networks. Additionally, CSgateway node(s) 512 can access mobility, or roaming, data generatedthrough SS7 network 560; for instance, mobility data stored in a visitedlocation register (VLR), which can reside in memory 530. Moreover, CSgateway node(s) 512 interfaces CS-based traffic and signaling and PSgateway node(s) 518. As an example, in a 3GPP UMTS network, CS gatewaynode(s) 512 can be realized at least in part in gateway GPRS supportnode(s) (GGSN). It should be appreciated that functionality and specificoperation of CS gateway node(s) 512, PS gateway node(s) 518, and servingnode(s) 516, is provided and dictated by radio technology(ies) utilizedby mobile network platform 510 for telecommunication over a radio accessnetwork 520 with other devices, such as a radiotelephone 575.

In addition to receiving and processing CS-switched traffic andsignaling, PS gateway node(s) 518 can authorize and authenticatePS-based data sessions with served mobile devices. Data sessions cancomprise traffic, or content(s), exchanged with networks external to themobile network platform 510, like wide area network(s) (WANs) 550,enterprise network(s) 570, and service network(s) 580, which can beembodied in local area network(s) (LANs), can also be interfaced withmobile network platform 510 through PS gateway node(s) 518. It is to benoted that WANs 550 and enterprise network(s) 570 can embody, at leastin part, a service network(s) like IP multimedia subsystem (IMS). Basedon radio technology layer(s) available in technology resource(s) orradio access network 520, PS gateway node(s) 518 can generate packetdata protocol contexts when a data session is established; other datastructures that facilitate routing of packetized data also can begenerated. To that end, in an aspect, PS gateway node(s) 518 cancomprise a tunnel interface (e.g., tunnel termination gateway (TTG) in3GPP UMTS network(s) (not shown)) which can facilitate packetizedcommunication with disparate wireless network(s), such as Wi-Finetworks.

In embodiment 500, mobile network platform 510 also comprises servingnode(s) 516 that, based upon available radio technology layer(s) withintechnology resource(s) in the radio access network 520, convey thevarious packetized flows of data streams received through PS gatewaynode(s) 518. It is to be noted that for technology resource(s) that relyprimarily on CS communication, server node(s) can deliver trafficwithout reliance on PS gateway node(s) 518; for example, server node(s)can embody at least in part a mobile switching center. As an example, ina 3GPP UMTS network, serving node(s) 516 can be embodied in serving GPRSsupport node(s) (SGSN).

For radio technologies that exploit packetized communication, server(s)514 in mobile network platform 510 can execute numerous applicationsthat can generate multiple disparate packetized data streams or flows,and manage (e.g., schedule, queue, format . . . ) such flows. Suchapplication(s) can comprise add-on features to standard services (forexample, provisioning, billing, customer support . . . ) provided bymobile network platform 510. Data streams (e.g., content(s) that arepart of a voice call or data session) can be conveyed to PS gatewaynode(s) 518 for authorization/authentication and initiation of a datasession, and to serving node(s) 516 for communication thereafter. Inaddition to application server, server(s) 514 can comprise utilityserver(s), a utility server can comprise a provisioning server, anoperations and maintenance server, a security server that can implementat least in part a certificate authority and firewalls as well as othersecurity mechanisms, and the like. In an aspect, security server(s)secure communication served through mobile network platform 510 toensure network's operation and data integrity in addition toauthorization and authentication procedures that CS gateway node(s) 512and PS gateway node(s) 518 can enact. Moreover, provisioning server(s)can provision services from external network(s) like networks operatedby a disparate service provider; for instance, WAN 550 or GlobalPositioning System (GPS) network(s) (not shown). Provisioning server(s)can also provision coverage through networks associated to mobilenetwork platform 510 (e.g., deployed and operated by the same serviceprovider), such as distributed antenna networks that enhance wirelessservice coverage by providing more network coverage.

It is to be noted that server(s) 514 can comprise one or more processorsconfigured to confer at least in part the functionality of mobilenetwork platform 510. To that end, the one or more processor can executecode instructions stored in memory 530, for example. It is to beappreciated that server(s) 514 can comprise a content manager, whichoperates in substantially the same manner as described hereinbefore.

In example embodiment 500, memory 530 can store information related tooperation of mobile network platform 510. Other operational informationcan comprise provisioning information of mobile devices served throughmobile network platform 510, subscriber databases; applicationintelligence, pricing schemes, e.g., promotional rates, flat-rateprograms, couponing campaigns; technical specification(s) consistentwith telecommunication protocols for operation of disparate radio, orwireless, technology layers; and so forth. Memory 530 can also storeinformation from at least one of telephony network(s) 540, WAN 550, SS7network 560, or enterprise network(s) 570. In an aspect, memory 530 canbe, for example, accessed as part of a data store component or as aremotely connected memory store.

In order to provide a context for the various aspects of the disclosedsubject matter, FIG. 5, and the following discussion, are intended toprovide a brief, general description of a suitable environment in whichthe various aspects of the disclosed subject matter can be implemented.While the subject matter has been described above in the general contextof computer-executable instructions of a computer program that runs on acomputer and/or computers, those skilled in the art will recognize thatthe disclosed subject matter also can be implemented in combination withother program modules. Generally, program modules comprise routines,programs, components, data structures, etc. that perform particulartasks and/or implement particular abstract data types.

Turning now to FIG. 6, an illustrative embodiment of a communicationdevice 600 is shown. The communication device 600 can serve as anillustrative embodiment of various devices and/or components describedherein, such as base stations, RRHs, antenna systems, and/or the like;data terminals 114, mobile devices 124, vehicle 126, display devices144, or other client devices for communication via communicationsnetwork 125; etc. For example, computing device 600 can facilitate, inwhole or in part, detection of interference/PIM in a communicationssystem and performing of action(s), such as polarization adjustingand/or phase shifting/delaying, as described herein, that result inmitigation/cancellation of the interference/PIM.

The communication device 600 can comprise a wireline and/or wirelesstransceiver 602 (herein transceiver 602), a user interface (UI) 604, apower supply 614, a location receiver 616, a motion sensor 618, anorientation sensor 620, and a controller 606 for managing operationsthereof. The transceiver 602 can support short-range or long-rangewireless access technologies such as Bluetooth®, ZigBee®, WiFi, DECT, orcellular communication technologies, just to mention a few (Bluetooth®and ZigBee® are trademarks registered by the Bluetooth® Special InterestGroup and the ZigBee® Alliance, respectively). Cellular technologies caninclude, for example, CDMA-1X, UMTS/HSDPA, GSM/GPRS, TDMA/EDGE, EV/DO,WiMAX, SDR, LTE, as well as other next generation wireless communicationtechnologies as they arise. The transceiver 602 can also be adapted tosupport circuit-switched wireline access technologies (such as PSTN),packet-switched wireline access technologies (such as TCP/IP, VoIP,etc.), and combinations thereof.

The UI 604 can include a depressible or touch-sensitive keypad 608 witha navigation mechanism such as a roller ball, a joystick, a mouse, or anavigation disk for manipulating operations of the communication device600. The keypad 608 can be an integral part of a housing assembly of thecommunication device 600 or an independent device operably coupledthereto by a tethered wireline interface (such as a USB cable) or awireless interface supporting for example Bluetooth®. The keypad 608 canrepresent a numeric keypad commonly used by phones, and/or a QWERTYkeypad with alphanumeric keys. The UI 604 can further include a display610 such as monochrome or color LCD (Liquid Crystal Display), OLED(Organic Light Emitting Diode) or other suitable display technology forconveying images to an end user of the communication device 600. In anembodiment where the display 610 is touch-sensitive, a portion or all ofthe keypad 608 can be presented by way of the display 610 withnavigation features.

The display 610 can use touch screen technology to also serve as a userinterface for detecting user input. As a touch screen display, thecommunication device 600 can be adapted to present a user interfacehaving graphical user interface (GUI) elements that can be selected by auser with a touch of a finger. The display 610 can be equipped withcapacitive, resistive or other forms of sensing technology to detect howmuch surface area of a user's finger has been placed on a portion of thetouch screen display. This sensing information can be used to controlthe manipulation of the GUI elements or other functions of the userinterface. The display 610 can be an integral part of the housingassembly of the communication device 600 or an independent devicecommunicatively coupled thereto by a tethered wireline interface (suchas a cable) or a wireless interface.

The UI 604 can also include an audio system 612 that utilizes audiotechnology for conveying low volume audio (such as audio heard inproximity of a human ear) and high volume audio (such as speakerphonefor hands free operation). The audio system 612 can further include amicrophone for receiving audible signals of an end user. The audiosystem 612 can also be used for voice recognition applications. The UI604 can further include an image sensor 613 such as a charged coupleddevice (CCD) camera for capturing still or moving images.

The power supply 614 can utilize common power management technologiessuch as replaceable and rechargeable batteries, supply regulationtechnologies, and/or charging system technologies for supplying energyto the components of the communication device 600 to facilitatelong-range or short-range portable communications. Alternatively, or incombination, the charging system can utilize external power sources suchas DC power supplied over a physical interface such as a USB port orother suitable tethering technologies.

The location receiver 616 can utilize location technology such as aglobal positioning system (GPS) receiver capable of assisted GPS foridentifying a location of the communication device 600 based on signalsgenerated by a constellation of GPS satellites, which can be used forfacilitating location services such as navigation. The motion sensor 618can utilize motion sensing technology such as an accelerometer, agyroscope, or other suitable motion sensing technology to detect motionof the communication device 600 in three-dimensional space. Theorientation sensor 620 can utilize orientation sensing technology suchas a magnetometer to detect the orientation of the communication device600 (north, south, west, and east, as well as combined orientations indegrees, minutes, or other suitable orientation metrics).

The communication device 600 can use the transceiver 602 to alsodetermine a proximity to a cellular, WiFi, Bluetooth®, or other wirelessaccess points by sensing techniques such as utilizing a received signalstrength indicator (RSSI) and/or signal time of arrival (TOA) or time offlight (TOF) measurements. The controller 606 can utilize computingtechnologies such as a microprocessor, a digital signal processor (DSP),programmable gate arrays, application specific integrated circuits,and/or a video processor with associated storage memory such as Flash,ROM, RAM, SRAM, DRAM or other storage technologies for executingcomputer instructions, controlling, and processing data supplied by theaforementioned components of the communication device 600.

Other components not shown in FIG. 6 can be used in one or moreembodiments of the subject disclosure. For instance, the communicationdevice 600 can include a slot for adding or removing an identity modulesuch as a Subscriber Identity Module (SIM) card or Universal IntegratedCircuit Card (UICC). SIM or UICC cards can be used for identifyingsubscriber services, executing programs, storing subscriber data, and soon.

The terms “first,” “second,” “third,” and so forth, which may be used inthe claims, unless otherwise clear by context, is for clarity only anddoesn't otherwise indicate or imply any order in time. For instance, “afirst determination,” “a second determination,” and “a thirddetermination,” does not indicate or imply that the first determinationis to be made before the second determination, or vice versa, etc.

In the subject specification, terms such as “store,” “storage,” “datastore,” data storage,” “database,” and substantially any otherinformation storage component relevant to operation and functionality ofa component, refer to “memory components,” or entities embodied in a“memory” or components comprising the memory. It will be appreciatedthat the memory components described herein can be either volatilememory or nonvolatile memory, or can comprise both volatile andnonvolatile memory, by way of illustration, and not limitation, volatilememory, non-volatile memory, disk storage, and memory storage. Further,nonvolatile memory can be included in read only memory (ROM),programmable ROM (PROM), electrically programmable ROM (EPROM),electrically erasable ROM (EEPROM), or flash memory. Volatile memory cancomprise random access memory (RAM), which acts as external cachememory. By way of illustration and not limitation, RAM is available inmany forms such as synchronous RAM (SRAM), dynamic RAM (DRAM),synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhancedSDRAM (ESDRAM), Synchlink DRAM (SLDRAM), and direct Rambus RAM (DRRAM).Additionally, the disclosed memory components of systems or methodsherein are intended to comprise, without being limited to comprising,these and any other suitable types of memory.

Moreover, it will be noted that the disclosed subject matter can bepracticed with other computer system configurations, comprisingsingle-processor or multiprocessor computer systems, mini-computingdevices, mainframe computers, as well as personal computers, hand-heldcomputing devices (e.g., PDA, phone, smartphone, watch, tabletcomputers, netbook computers, etc.), microprocessor-based orprogrammable consumer or industrial electronics, and the like. Theillustrated aspects can also be practiced in distributed computingenvironments where tasks are performed by remote processing devices thatare linked through a communications network; however, some if not allaspects of the subject disclosure can be practiced on stand-alonecomputers. In a distributed computing environment, program modules canbe located in both local and remote memory storage devices.

Some of the embodiments described herein can also employ artificialintelligence (AI) to facilitate automating one or more featuresdescribed herein. One or more embodiments can employ various AI-basedschemes for carrying out various embodiments thereof. Moreover, aclassifier can be employed. A classifier is a function that maps aninput attribute vector, x=(x1, x2, x3, x4, . . . , xn), to a confidencethat the input belongs to a class, that is, f(x)=confidence (class).Such classification can employ a probabilistic and/or statistical-basedanalysis (e.g., factoring into the analysis utilities and costs) todetermine or infer an action that a user desires to be automaticallyperformed. A support vector machine (SVM) is an example of a classifierthat can be employed. The SVM operates by finding a hypersurface in thespace of possible inputs, which the hypersurface attempts to split thetriggering criteria from the non-triggering events. Intuitively, thismakes the classification correct for testing data that is near, but notidentical to, training data. Other directed and undirected modelclassification approaches comprise, e.g., naïve Bayes, Bayesiannetworks, decision trees, neural networks, fuzzy logic models, andprobabilistic classification models providing different patterns ofindependence. Classification as used herein also is inclusive ofstatistical regression that is utilized to develop models of priority.

As will be readily appreciated, one or more of the embodiments canemploy classifiers that are explicitly trained (e.g., via a generictraining data) as well as implicitly trained (e.g., via observing UEbehavior, operator preferences, historical information, receivingextrinsic information). For example, SVMs can be configured via alearning or training phase within a classifier constructor and featureselection module. Thus, the classifier(s) can be used to automaticallylearn and perform a number of functions, including but not limited todetermining according to predetermined criteria which of the acquiredcell sites will benefit a maximum number of subscribers and/or which ofthe acquired cell sites will add minimum value to the existingcommunications network coverage, etc.

As used in some contexts in this application, in some embodiments, theterms “component,” “system” and the like are intended to refer to, orcomprise, a computer-related entity or an entity related to anoperational apparatus with one or more specific functionalities, whereinthe entity can be either hardware, a combination of hardware andsoftware, software, or software in execution. As an example, a componentmay be, but is not limited to being, a process running on a processor, aprocessor, an object, an executable, a thread of execution,computer-executable instructions, a program, and/or a computer. By wayof illustration and not limitation, both an application running on aserver and the server can be a component. One or more components mayreside within a process and/or thread of execution and a component maybe localized on one computer and/or distributed between two or morecomputers. In addition, these components can execute from variouscomputer readable media having various data structures stored thereon.The components may communicate via local and/or remote processes such asin accordance with a signal having one or more data packets (e.g., datafrom one component interacting with another component in a local system,distributed system, and/or across a network such as the Internet withother systems via the signal). As another example, a component can be anapparatus with specific functionality provided by mechanical partsoperated by electric or electronic circuitry, which is operated by asoftware or firmware application executed by a processor, wherein theprocessor can be internal or external to the apparatus and executes atleast a part of the software or firmware application. As yet anotherexample, a component can be an apparatus that provides specificfunctionality through electronic components without mechanical parts,the electronic components can comprise a processor therein to executesoftware or firmware that confers at least in part the functionality ofthe electronic components. While various components have beenillustrated as separate components, it will be appreciated that multiplecomponents can be implemented as a single component, or a singlecomponent can be implemented as multiple components, without departingfrom example embodiments.

Further, the various embodiments can be implemented as a method,apparatus or article of manufacture using standard programming and/orengineering techniques to produce software, firmware, hardware or anycombination thereof to control a computer to implement the disclosedsubject matter. The term “article of manufacture” as used herein isintended to encompass a computer program accessible from anycomputer-readable device or computer-readable storage/communicationsmedia. For example, computer readable storage media can include, but arenot limited to, magnetic storage devices (e.g., hard disk, floppy disk,magnetic strips), optical disks (e.g., compact disk (CD), digitalversatile disk (DVD)), smart cards, and flash memory devices (e.g.,card, stick, key drive). Of course, those skilled in the art willrecognize many modifications can be made to this configuration withoutdeparting from the scope or spirit of the various embodiments.

In addition, the words “example” and “exemplary” are used herein to meanserving as an instance or illustration. Any embodiment or designdescribed herein as “example” or “exemplary” is not necessarily to beconstrued as preferred or advantageous over other embodiments ordesigns. Rather, use of the word example or exemplary is intended topresent concepts in a concrete fashion. As used in this application, theterm “or” is intended to mean an inclusive “or” rather than an exclusive“or”. That is, unless specified otherwise or clear from context, “Xemploys A or B” is intended to mean any of the natural inclusivepermutations. That is, if X employs A; X employs B; or X employs both Aand B, then “X employs A or B” is satisfied under any of the foregoinginstances. In addition, the articles “a” and “an” as used in thisapplication and the appended claims should generally be construed tomean “one or more” unless specified otherwise or clear from context tobe directed to a singular form.

Moreover, terms such as “user equipment,” “mobile station,” “mobile,”subscriber station,” “access terminal,” “terminal,” “handset,” “mobiledevice” (and/or terms representing similar terminology) can refer to awireless device utilized by a subscriber or user of a wirelesscommunication service to receive or convey data, control, voice, video,sound, gaming or substantially any data-stream or signaling-stream. Theforegoing terms are utilized interchangeably herein and with referenceto the related drawings.

Furthermore, the terms “user,” “subscriber,” “customer,” “consumer” andthe like are employed interchangeably throughout, unless contextwarrants particular distinctions among the terms. It should beappreciated that such terms can refer to human entities or automatedcomponents supported through artificial intelligence (e.g., a capacityto make inference based, at least, on complex mathematical formalisms),which can provide simulated vision, sound recognition and so forth.

As employed herein, the term “processor” can refer to substantially anycomputing processing unit or device comprising, but not limited tocomprising, single-core processors; single-processors with softwaremultithread execution capability; multi-core processors; multi-coreprocessors with software multithread execution capability; multi-coreprocessors with hardware multithread technology; parallel platforms; andparallel platforms with distributed shared memory. Additionally, aprocessor can refer to an integrated circuit, an application specificintegrated circuit (ASIC), a digital signal processor (DSP), a fieldprogrammable gate array (FPGA), a programmable logic controller (PLC), acomplex programmable logic device (CPLD), a discrete gate or transistorlogic, discrete hardware components or any combination thereof designedto perform the functions described herein. Processors can exploitnano-scale architectures such as, but not limited to, molecular andquantum-dot based transistors, switches and gates, in order to optimizespace usage or enhance performance of user equipment. A processor canalso be implemented as a combination of computing processing units.

What has been described above includes mere examples of variousembodiments. It is, of course, not possible to describe everyconceivable combination of components or methodologies for purposes ofdescribing these examples, but one of ordinary skill in the art canrecognize that many further combinations and permutations of the presentembodiments are possible. Accordingly, the embodiments disclosed and/orclaimed herein are intended to embrace all such alterations,modifications and variations that fall within the spirit and scope ofthe appended claims. Furthermore, to the extent that the term “includes”is used in either the detailed description or the claims, such term isintended to be inclusive in a manner similar to the term “comprising” as“comprising” is interpreted when employed as a transitional word in aclaim.

In addition, a flow diagram may include a “start” and/or “continue”indication. The “start” and “continue” indications reflect that thesteps presented can optionally be incorporated in or otherwise used inconjunction with other routines. In this context, “start” indicates thebeginning of the first step presented and may be preceded by otheractivities not specifically shown. Further, the “continue” indicationreflects that the steps presented may be performed multiple times and/ormay be succeeded by other activities not specifically shown. Further,while a flow diagram indicates a particular ordering of steps, otherorderings are likewise possible provided that the principles ofcausality are maintained.

As may also be used herein, the term(s) “operably coupled to”, “coupledto”, and/or “coupling” includes direct coupling between items and/orindirect coupling between items via one or more intervening items. Suchitems and intervening items include, but are not limited to, junctions,communication paths, components, circuit elements, circuits, functionalblocks, and/or devices. As an example of indirect coupling, a signalconveyed from a first item to a second item may be modified by one ormore intervening items by modifying the form, nature or format ofinformation in a signal, while one or more elements of the informationin the signal are nevertheless conveyed in a manner than can berecognized by the second item. In a further example of indirectcoupling, an action in a first item can cause a reaction on the seconditem, as a result of actions and/or reactions in one or more interveningitems.

Although specific embodiments have been illustrated and describedherein, it should be appreciated that any arrangement which achieves thesame or similar purpose may be substituted for the embodiments describedor shown by the subject disclosure. The subject disclosure is intendedto cover any and all adaptations or variations of various embodiments.Combinations of the above embodiments, and other embodiments notspecifically described herein, can be used in the subject disclosure.For instance, one or more features from one or more embodiments can becombined with one or more features of one or more other embodiments. Inone or more embodiments, features that are positively recited can alsobe negatively recited and excluded from the embodiment with or withoutreplacement by another structural and/or functional feature. The stepsor functions described with respect to the embodiments of the subjectdisclosure can be performed in any order. The steps or functionsdescribed with respect to the embodiments of the subject disclosure canbe performed alone or in combination with other steps or functions ofthe subject disclosure, as well as from other embodiments or from othersteps that have not been described in the subject disclosure. Further,more than or less than all of the features described with respect to anembodiment can also be utilized.

The foregoing embodiments can be combined in whole or in part with theembodiments described in U.S. Pat. No. 10,284,313 (issued on May 7,2019). For instance, embodiments of the aforementioned U.S. patent canbe combined in whole or in part with embodiments of the subjectdisclosure. For example, one or more features and/or embodimentsdescribed in the aforementioned U.S. patent can be used in conjunctionwith (or as a substitute for) one or more features and/or embodimentsdescribed herein, and vice versa. Accordingly, all sections of theaforementioned U.S. patent are incorporated herein by reference in theirentirety.

What is claimed is:
 1. A device, comprising: a processing systemincluding a processor and associated with an antenna system; and amemory that stores executable instructions that, when executed by theprocessing system, facilitate performance of operations, the operationscomprising: obtaining data regarding interference detected in a receivedcommunication signal; and performing polarization adjusting by rotatingone or more radiating elements of the antenna system such that an impactof the interference on the antenna system is minimized.
 2. The device ofclaim 1, wherein the interference originates in a near field region ofthe antenna system or an intermediate field region of the antenna systemthat spans a portion of the near field region and a portion of a farfield region of the antenna system.
 3. The device of claim 1, whereinthe performing the polarization adjusting results in no impact to a farfield region of the antenna system, as compared to a case where thepolarization adjusting is not performed.
 4. The device of claim 1,wherein the interference comprises passive intermodulation (PIM).
 5. Thedevice of claim 1, wherein the polarization adjusting comprises rotatinga subset of the radiating elements of the antenna system.
 6. A method,comprising: obtaining data regarding interference originating from oneor more interference sources; and mitigating, by an adjusting mechanismassociated with an antenna system, the interference by performingpolarization adjusting via rotation of radiating elements of the antennasystem.
 7. The method of claim 6, wherein the interference originates ina near field region of the antenna system or an intermediate fieldregion of the antenna system that spans a portion of the near fieldregion and a portion of a far field region of the antenna system.
 8. Themethod of claim 6, wherein the performing the polarization adjustingresults in no impact to a far field region of the antenna system, ascompared to a case where the polarization adjusting is not performed. 9.The method of claim 6, wherein the interference comprises passiveintermodulation (PIM).
 10. The method of claim 6, wherein the radiatingelements comprise orthogonally-polarized element pairs.
 11. The methodof claim 6, wherein the antenna system comprises a plurality ofantennas, and wherein the radiating elements are included in one antennaof the plurality of antennas.
 12. The method of claim 6, wherein theantenna system comprises a single antenna having a plurality ofradiating elements, and wherein the radiating elements comprise a subsetof the plurality of radiating elements.
 13. The method of claim 6,wherein the polarization adjusting comprises rotating a first set ofradiating elements by a first angle of rotation and a second set ofradiating elements by a second angle of rotation.
 14. The method ofclaim 6, wherein the polarization adjusting is performed by a remoteradio unit.
 15. The method of claim 6, wherein the polarizationadjusting involves controlling one or more motors.
 16. The method ofclaim 6, wherein the polarization adjusting is performed via one or moreAntenna Interface Standards Group (AISG)-based interfaces.
 17. Themethod of claim 6, wherein the obtaining is performed by a processingsystem including a processor, and wherein the adjusting mechanism isincluded in or comprises the processing system.
 18. A non-transitorymachine-readable medium, comprising executable instructions that, whenexecuted by a processing system including a processor and associatedwith an antenna system, facilitate performance of operations, theoperations comprising: receiving data regarding interference present ina received communication signal; and performing polarization adjustingby causing one or more radiating elements of the antenna system to berotated such that the interference is mitigated.
 19. The non-transitorymachine-readable medium of claim 18, wherein the performing thepolarization adjusting results in no impact to a far field region of theantenna system, as compared to a case where the polarization adjustingis not performed.
 20. The non-transitory machine-readable medium ofclaim 18, wherein the polarization adjusting comprises rotating a subsetof the radiating elements of the antenna system.